What To Expect During a Puppy’s First 12 Weeks of Life

Matt Matasci Matt Matasci · Updated: August 23, 2023 / Published: May 30, 2022

Raising a puppy is one of life’s most rewarding — and challenging — experiences. You’ll be in love from the moment the roly-poly newborns emerge from their mother to the day they each arrive at their forever home and beyond. In order to raise a happy, healthy and well-adjusted dog, it’s extremely important for the breeder and owner to work together on training, socialization and nutrition during the first 12 weeks of a puppy’s life.

Young dogs are such vulnerable, impressionable creatures. The first few months are the time that a puppy develops the attributes that define them as an adult dog. But don’t stress out! Whether you’re a breeder or a new owner, correctly training a puppy is a challenging but completely attainable endeavor. Technology is on your side; there are several pet apps that track training and socialization progress during the first months of a puppy’s life.

Our guide serves as a resource for breeders and new puppy owners so they can work hand-in-hand to successfully raise a puppy.

Pet Shipping with CitizenShipper
Get Paid to Drive with CitizenShipper
Treats are a great motivator when training a 12 week old or younger puppy.

Socializing and Training a 12 Week Old Puppy

Start with the Basics

Don’t dive right into the deep-end without learning how to doggy-paddle! Start slowly and stick to the basics when you’re training a puppy. Start with simple commands. As the puppy masters each command, work your way into more complicated training.

  • Right away, call the puppy by name. As he learns his name and comes when called, reward him with treats.
  • Next, collar and leash training. Start off with the collar and once the puppy is accustomed to it, attach the leash. Your puppy shouldn’t go on walks or be outside where other dogs have been until it’s fully vaccinated.
  • It will take some time for the puppy to get used to a leash attached to the collar. Allow the puppy to drag the leash around the house — just be sure to constantly supervise him.
  • Once he’s comfortable with collar and leash (and vaccinated), you can start going for walks! Remember, start with short walks and gradually build up the distance.
  • After he masters the basics at around five weeks, start with more complicated commands like sit, stay and down.

A puppy’s brain is very unique between 12 and 14 weeks — during this time, it permanently changes. Good behaviors that are rewarded will remain; that goes for bad habits as well.

Whatever you do, don’t express frustration or anger if training is taking longer than expected. All dogs learn at a different pace. A 12 week old puppy can become overwhelmed by new information — don’t fret, if you keep at it with a positive, calm and nurturing attitude, he will pick it up eventually.

A calm environment is the most conducive to learning for puppies. A negative, angry environment could cause the puppy to develop problematic personality traits as an adult. The early training work from a breeder sets the puppy up for successful, focused training from its permanent owner.

Why Socialization During the First 12 Weeks Is So Critical

Like training, socializing a puppy is a team effort. The initial work by the breeder sets the stage before passing the baton to the buyer. One way for breeders to help their carefully-screened buyers is by providing a thoughtfully-curated puppy kit. This kit can include training guides, puppy food and even dog toys.

Just as a responsible breeder always completes the required health screenings before breeding, they also know to start the puppy training process early. Addressing any potential behavioral issues right away sets the puppy up for success once she’s in her permanent home.

The Identification System

During the first weeks of life, a puppy’s visual cortex develops an identification system. This system helps her identify what social partners look like and dictates how she’ll respond. These social partners are every living creature the puppy interacts with — human beings like you, your family and the mailman, or other animals like dogs, cats, squirrels and so on.

The thing is, once this identification is hardwired, it’s essentially permanently set. It’s very difficult for dogs to socially accept an “unknown” species after the 12-14 week mark. That’s not just referring to new types of animals she’s never seen before. It could be types of people or even unknown experiences and sounds that give the puppy anxiety.

One helpful guideline is the “Rule of 12.” This popular puppy-rearing tip suggests that, by 12 weeks of age, a puppy should have:

  • Met and played with 12 different types of people outside the family, like men, women, people in wheelchairs, people with different skin tones, men with deep voices, etc.
  • Experienced 12 different surfaces, like wood, sand, grass, carpet, mud, concrete, wet grass, etc.
  • Played with 12 different objects, like fuzzy toys, balls, squeaky toys, wooden toys, etc.
  • Been in 12 different locations, such as the front yard, back yard, inside your house, inside a friend’s house, within a moving car, at a lake, etc.
  • Been exposed to 12 different fast moving objects, like adults and children running, someone skateboarding, a motorcycle, bicycles, cars, etc. Don’t let the puppy chase these objects!
  • Heard 12 different noises, such as a doorbell, kids playing, skateboards, motorcycles, the dishwasher, a lawn mower, a vacuum, etc. Always monitor the puppy’s comfort level; you don’t want her to get scared.

Fear Stages

Most puppies go through what is called “fear stages” or “fear periods.” The first fear stage happens around eight weeks of age and the second between six and 14 months — larger breeds tend to have their second fear stage later. Fear periods are a completely normal, inevitable part of a puppy’s life-cycle. You can’t prevent them with increased socialization.

  • During the first fear stage, the puppy will be very timid and anxious. Objects or experiences may concern him more than before — even if he’s already experienced them!
  • Often, the first fear stage tends to happen right around the time a puppy is transitioning into its forever home.
  • With proper socialization, this anxiety will lessen and the puppy will be confident and feel secure.
  • During the fear period, you should still socialize the puppy, but be thoughtful about your approach.
  • Don’t pressure or force the puppy to confront something frightening — this can backfire and cause lifelong fear.

So what’s the best way to deal with a scary situation? The American Kennel Club has a great step-by-step approach to handling these moments:

  1. Move: Put some distance between the puppy and what’s scaring him.
  2. Praise: Give your puppy praise and reward him. The reward is for looking to you for guidance and looking at/experiencing the object or sound that scared him.
  3. Explore: Allow the puppy to have control over how close he gets to the source of his fear. Again, don’t try to trick him into getting closer — the puppy should be in charge and feel secure. You should reward him for any positive curiosity he displays.
  4. Keep It Short: Even if he doesn’t overcome his fear in one training session, keep it short and positive. Reward him with lots of treats and praise when the session ends.
  5. Incorporate: Make a note of what frightens the puppy and incorporate it into future training sessions. Eventually he’ll overcome his fears if you take the right approach.

Preventing Resource Guarding

Every dog owner has experienced resource guarding. Maybe you got a little too close to her food bowl while she’s eating, or tried to take away a toy before she was ready — the snarls and growls commence and worst-case, she even snaps at you. This behavior can be prevented with proper social training as a puppy.

  • Reduce competition between puppies by feeding them in separate bowls. Communal bowls can lead to food anxiety, which in turn can result in resource guarding.
  • Encourage trading — use a toy or a treat to make a trade for the toy your puppy’s currently playing with or chewing on.
  • One great way to get them used to people being near their food is dropping treats as you walk by their bowl.
  • Teach your puppy the “leave it” command — this command is useful for more than just getting them to give up toys or food.
Make sure your 12 week old puppy is getting enough sleep.

Puppy Health Tips for the First 12 Weeks

Sleep Habits of a 12 Week Old Puppy

Just like human babies, puppies sleep a lot! When we say a lot, we mean they’ll be napping almost all day. And, just like new parents are recommended to set up a daily routine for their baby, puppy owners should establish a sleeping, walking, playing and feeding schedule. How long should you expect your pup to be snoozing each day?

  • 8-9 weeks — 20 hours of sleep per day
  • 10-12 weeks — 18-20 hours of sleep per day
  • 13-20 weeks — 15-18 hours of sleep per day
  • 1 year — 10-13 hours

As you can see, most of the day your puppy will be napping! Don’t wake him up if you want to play with him, you think he’s sleeping too much or you want to feed him.


  • Puppies develop at a very quick rate; one year of development for a dog is equal to 18 years for a human!
  • Sleep provides the puppy with the energy he needs to develop his skeletal, muscular and nervous systems.
  • When a puppy doesn’t get enough sleep during his first few weeks, it can result in increased stress, anxiety and aggression, among other issues.

Nighttime Sleep Habits for Puppies

At night, allow your puppy to sleep as long as he needs. However, if he wakes up in the night, it means he needs a potty break. If there’s a pattern of waking in the night, set an alarm for a few minutes prior to when he usually wakes up. That way, he isn’t whining or barking to alert you of his needs.

  • Don’t take this time to play with the puppy or even pay much attention to him. Otherwise, you risk disrupting sleep patterns.
  • Most dog experts recommend crate training puppies, especially at night. The crate is comforting to puppies and makes the bedtime routine easier.
  • Make the crate comfortable and inviting by lining it with soft, felted blankets. Placing the crate in your own bedroom helps him feel comforted that his family is nearby.
  • Keep a set bedtime — it doesn’t really matter what time, but stay consistent.
  • The bedroom should have low lighting and remain quiet — this will give the puppy a cue that it’s bedtime.
  • Don’t give in to his protests — young puppies may whine or bark before settling down. Stay strong!
  • While your puppy will take plenty of naps during the day, he’ll also need to get lots of exercise to use up all that energy!

Daytime Sleep Habits for Puppies

  • It’s recommended that the puppy takes naps in his crate.
  • The puppy will likely need to take his first nap of the day around mid-morning, after a short walk and breakfast.
  • The next nap should be in the mid-afternoon after going out for another walk, playing and training.
  • If your puppy takes more than two naps a day, that’s okay! Some puppies nap as much as once an hour, with naps lasting between 30 minutes and two hours.
House training a 12 week old puppy is challenging but very important!

House Training Tips for Puppies Under 12 Weeks Old

In addition to socializing your puppy right away, house training should begin immediately. It’s important to remember that puppies have very little bladder control up until about 12 weeks, so there will be a lot of trial and error.

  • Be compassionate when your puppy has an accident — getting mad at her won’t help anything. In fact, it’ll just exacerbate the issue and lead to behavioral issues down the road.
  • There are three common methods for house training a puppy: Crate Training, Paper Training and Indoor Potty Training.

Crate Training

As we mentioned above, dogs don’t see their crate as a prison or a cage — in fact, it’s a “safe space” and source of comfort.

  • Some puppies may prefer sleeping in the dark; for them, an enclosed, kennel-style crate is best. For most other dogs, a metal wire crate will do the trick.
  • It’s best to buy a crate that’s appropriately sized for the puppy when she’s full-sized (unless you have the resources to buy new crates as the puppy grows). You can buy a divider that partitions the crate into an appropriately-sized space for your little pup.
  • Try to associate the crate with relaxation time. Don’t ‌put the puppy in her crate in the middle of playtime.
  • Work gradually; the puppy may initially only stay in the crate for 10 minutes at a time. Build up incrementally until the puppy stays in her crate for hours at a time.
  • Reward the puppy when she goes into the crate. Positive association is the best tactic for training a young dog.
  • Like with everything in this guide, it’s important to stay patient. You may feel like you’re making a lot of progress when suddenly she regresses. Don’t get frustrated because as long as you stay calm, chances are she’ll eventually become comfortable.

Potty Pads

While going potty outside is preferable, there may be certain situations in which potty pads or indoor potties can be used. It could be a case of convenience or safety:

  • Puppies pee a lot; if you’re an apartment dweller indoor training cuts down on the number of trips you make outside each day.
  • Maybe you live somewhere that’s icy cold in the winter or scorching hot in the summer — in those cases it may be safer or more comfortable for the pup to do her business inside.
  • If your puppy isn’t vaccinated and her potty place is in a public space, it may be a matter of safety to reduce exposure to potential health hazards.
  • Take your puppy to the pad or indoor potty frequently — even as frequently as every 15 minutes. Better safe than sorry!
  • Keep an eye out for visual cues that she needs to pee, like sniffing the ground or circling. Whining is another obvious cue.

Puppy Teething

The teething process for puppies is very similar to that of humans. Puppies are born without teeth and around three weeks of age, their deciduous teeth begin to erupt. Though unlike humans who have their baby teeth for years, the secondary teeth begin to replace the “milk teeth” by about 12 weeks of age.

  • Puppies experience a teething process that’s very similar to that of human babies.
  • He may drool excessively, express irritability, eat less than normal, paw at his mouth in discomfort and chew on anything and everything.
  • The chewing and gnawing helps encourage the adult teeth to break through the gums.
  • If you see blood on his toys, don’t worry. This is normal for a teething puppy.
  • You may find hollow shells of his baby teeth, but most of the time they’re swallowed while the puppy is eating. Don’t worry, this is totally safe!

Puppy Breath

Anyone who has had a puppy will know what we’re talking about when we mention puppy breath. It’s a unique smell that puppies have in their early weeks, and it’s associated with teething.

Yes, it’s smelly — descriptions of the smell vary but some owners have called it peppery, sweet, warm and clean. The bottom line is that if you’re a puppy lover, chances are you’ll associate the smell of puppy breath with feelings of love, innocence and comfort.

Persistent Tooth

Persistent tooth is a complication of teething that can result in an abnormal bite as the puppy matures.

  • A persistent tooth occurs when the milk tooth is still present and the permanent tooth begins to grow into place.
  • The permanent tooth can’t occupy the place in which it belongs, so it erupts abnormally.
  • VCA Animal Hospitals recommend that if you notice a persistent deciduous tooth to call your vet as soon as possible.
  • The vet will extract the baby tooth so the permanent tooth can properly grow into place.
  • If you take too long to act, the permanent tooth may grow into the wrong spot, which could necessitate the vet removing several permanent teeth.
Nutrition is important during the first 12 weeks of a puppy's life.

Early Life Nutrition for a 12 Week Old and Younger Puppy

Knowing what, how often and how much to feed your puppy through every stage of its early life can be overwhelming. Good nutrition is as important to your puppy’s long-term health and happiness as training and socialization. Be sure to weigh the puppy every day and keep track of her progress — as we mentioned at the top of the post, pet apps make tracking growth so much easier.

First Month

During the first month of a puppy’s life, the best nutrition is mother’s milk. In the rare case when a puppy can’t nurse from her mother or you need to supplement her diet, you can feed her puppy formula using a bottle. Be very careful about how much, when and what you bottle-feed the puppy because you can cause illness or even death if done improperly.


Most puppies start weaning between three-six weeks of age and it’s complete between six-eight weeks. At this point, you can start to feed her softened kibble.

  • Soak kibble in some water or broth or water down wet food so it becomes softened to a soup-like texture.
  • If the puppy transitions to a new home during weaning, the owner should continue to feed her the same brand as the breeder. This avoids any issues in the puppy’s very delicate digestive system.


Once the puppy is weaned, you’ll start to feed her specially formulated puppy dog food that promotes growth.

  • Puppies need three meals a day, spaced evenly. Stick to a routine. Follow the recommended servings.
  • If the new owner wants to change the type/brand of food, wait until she’s acclimated to the new home.
  • No matter what, stick with high-quality puppy food.
  • Even when you follow the instructions on the dog food, be sure to weigh your puppy regularly to avoid them being underweight or overweight.
  • Keep treats to less than 10 percent of the puppy’s caloric intake.

Puppy’s First Vet Visit

At eight weeks you need to take the puppy in for his first visit to the vet! Prepare your puppy for the big day so that it’s a positive experience — there are a lot of new sights, smells and touches that the puppy isn’t used to.

  • When you’re petting your puppy, try to simulate the sort of touching that the vet will do during his first exam. Lift his tail, pick up his paws and look into his ears.
  • Practice riding in the car. Start by just sitting in the car and allowing him to play with a toy. Then try a very short car ride down the street or around the block. After you’ve established that car rides are fun, you can try longer and longer trips. Remember, keep him in his crate for these trips.
  • Schedule a “trial run” before the actual first appointment. Drop by for just a few minutes when the clinic isn’t busy so your puppy can meet the vet and staff and get a tour of the facilities. This will make the actual first visit much less stressful for your puppy.
  • This visit is when he’ll get his first core vaccines. As we mentioned before, keep your puppy isolated from unvaccinated dogs before he’s vaxxed.
  • The vet will give him a physical exam and he’ll undergo deworming treatment.
  • Bring all the medical records from the breeder.


The responsibility is great during the first 12 weeks of a puppy’s life. It’s not quite as demanding as raising a human child, but it’s not far behind — especially for a breeder taking care of multiple puppies in a litter! However, the reward of seeing a little fluff ball grow from a tiny, vulnerable baby into a rambunctious, loyal and loving young dog is a heartwarming experience few others can match.

Raising a puppy takes a lot of teamwork between the breeder and the new owner — sometimes the best teammates aren’t located nearby. When a breeder and owner need to bring in a third party to deliver the puppy, they need a transporter that will be on their team.

When you use the CitizenShipper marketplace for puppy transportation, you’ll be hiring a transporter that’s as passionate about dogs as you. Post your puppy transport on CitizenShipper today!

Leave a Reply

Your email address will not be published. Required fields are marked *