Puppy Behaviour by Age: What to Expect and How to Handle It

Watching your puppy grow is a joy, but their behaviour can change faster than a Sunshine Coast summer storm. One day they are a sleepy bundle of fluff, and the next, they are testing every boundary you have set. Understanding puppy behaviour by age helps you stay patient and proactive. In this guide, we break down what is normal at every milestone and how our fear-free training methods can help you navigate each stage with confidence.

Key takeaways

• Puppy behaviour is closely linked to physical and neurological development stages.
• The 8-12 week window is critical for fear-free socialisation and positive exposure.
• Teething peaks at 3-4 months; provide appropriate chewing outlets to save your furniture.
• Adolescence (6-12 months) is a normal phase of 'regression' and testing boundaries.
• Consistency and patience are vital; never use aversive or dominance-based training techniques.
• Social maturity usually occurs between 12 and 24 months, depending on the breed.

8 to 12 Weeks: The 'Sponge' Phase

When you first bring your puppy home at eight weeks, they are in a critical socialisation period. This is often called the 'sponge' phase because they soak up every experience like a dry towel. Their behaviour is driven by curiosity, but they are also incredibly sensitive to new sights and sounds. This is the most important window for positive exposure to the world around them.

During this stage, you can expect:

• Sleepiness: Puppies need 18–20 hours of sleep. If they get 'the zoomies' or start biting more than usual, they are likely overtired.
• Low Independence: They will likely follow you everywhere (the 'Velcro' stage). This is a natural survival instinct to stay near their caregivers.
• Exploration via Mouth: Since they don't have hands, they use their mouths to learn about textures. Everything goes in the mouth, from your toes to the rug.

Our Puppy School focuses heavily on this age group. We prioritise gentle socialisation over forced interactions. On the Sunshine Coast, this is the time to get them used to the sound of heavy rain on tin roofs or the sight of people in broad-brimmed hats and sunglasses. Always keep experiences positive and use high-value treats to build a 'bank account' of good associations.

3 to 4 Months: The Boundary Testers

By 12 to 16 weeks, your puppy is gaining physical strength and coordination. Their confidence is growing, and they might start wandering a little further from your side. This is often when owners notice their puppy 'ignoring' cues they seemed to know last week. It isn't spite; it is simply a brain that is becoming more interested in the wider world than in your handful of kibble.

Key behaviours at this age include:

• Teething Troubles: Adult teeth start pushing through, causing discomfort. You will see a significant increase in chewing behaviour. Provide plenty of cold or frozen chew toys to soothe their gums.
• The Second Fear Period: Around 14 weeks, some puppies go through a 'fear of the unknown'. A bin they walked past yesterday might suddenly look terrifying. Use a calm voice and let them investigate at their own pace.
• Increased Distractibility: Smells on the grass become more interesting than a 'sit' cue.

This is a great time to transition from the basics to more structured private training sessions. We focus on building focus amidst distractions. We also recommend checking with your local Sunshine Coast Council regarding registration and microchipping requirements, as most puppies are fully vaccinated by the end of this stage and ready to explore local parks safely.

5 to 6 Months: The Pre-Adolescent Stage

Think of this as the 'primary school' years. Your puppy is no longer a baby, but they aren't quite a teenager yet. Their energy levels are peaking, and their adult coat might start coming in. This is a high-energy phase where mental enrichment is just as important as physical exercise. If they aren't mentally tired, they will find their own (often destructive) ways to entertain themselves.

Behavours to watch for:

• The 'Flight' Instinct: You might notice your puppy suddenly stops coming when called. Their instinct to explore can override their desire to stay close. Keep them on a long lead in unfenced areas to prevent them from practicing 'running away'.
• Increased Barking: As they become more aware of their environment, they may start alert-barking at passers-by or birds in the garden.
• Refining Social Skills: They are learning how to play with other dogs properly. Not every dog wants to play, so teaching your puppy to 'disengage' is vital.

Focus on loose lead walking now. In our humid Queensland climate, early morning or late evening walks are best to avoid burnt paws on the pavement. Teaching your puppy to walk calmly beside you now will save your shoulders a lot of grief as they get heavier.

6 to 12 Months: The Adolescent 'Teenage' Months

Welcome to adolescence! This is often the most challenging period for puppy owners. Hormonal shifts are occurring, and the brain is undergoing significant rewiring. You might feel like your well-trained puppy has 'forgotten' everything. Rest assured, the training is still in there; it's just being temporarily blocked by a surge of hormones and a need for independence.

Common adolescent behaviours:

• Selective Hearing: They will decide if your request is worth their time based on what else is happening.
• Hyper-reactivity: They may overreact to things they previously ignored, like other dogs on leads or bicycles.
• Testing Strength: Pulling on the lead often becomes a major issue as they grow stronger and more determined to reach a scent.

Patience is your best tool here. Never resort to aversive tools like check chains or prong collars, as these can cause long-term fear and aggression during this sensitive developmental stage. Stick to our fear-free methods. If you are struggling, our online courses offer great refreshers on managing teenage behaviour from the comfort of your home.

12 to 24 Months: Reaching Social Maturity

Depending on the breed, most dogs reach social maturity between one and two years of age. Large breeds like Golden Retrievers or Great Danes take longer to mature than smaller breeds like Jack Russells. At this stage, their personality is largely 'set', and you will see a settling in their energy levels. They become more discerning about which dogs they want to play with, often preferring a few close 'friends' over a busy dog park environment.

What to expect as they mature:

• Settling Ability: They should find it easier to relax inside the house without constant supervision.
• Focus: Training becomes more consistent as their 'adult' brain takes over.
• Breed Instincts: This is when breed-specific traits (like herding, pointing, or guarding) often become more pronounced.

Keep up with enrichment. A mature dog still needs to use their nose and brain. Use snuffle mats, lick mats, or hide-and-seek games around your backyard. On the Sunshine Coast, we are lucky to have many dog-friendly cafes; this is the perfect age to practice 'settle' cues while you enjoy a coffee.

Frequently asked questions

When do puppies finally stop biting everything?

Most puppies stop 'mouthy' behaviour once their adult teeth are fully in, usually around six months. However, if they continue to bite to get attention or during play, they may need more training on 'bite inhibition'. Always redirect them to a toy and reward them for making the right choice. If it persists past 7–8 months, consider a private session to rule out over-arousal issues.

Why has my 8-month-old puppy stopped listening to me?

Your puppy is likely in the adolescent phase. Their brain is prioritising exploration and independence due to hormonal changes. They haven't 'forgotten' their training; they are just more easily distracted. Go back to basics, use higher-value treats (like small pieces of cooked chicken), and keep training sessions short and fun to keep them engaged.

Is it too late to start puppy school if my dog is 5 months old?

While traditional 'Puppy School' is for dogs under 16 weeks, it is never too late for training. For dogs over 4–5 months, we recommend our 'Teenage' or 'Manners' classes. These focus on the specific challenges of pre-adolescence, such as focus, lead walking, and coming when called under distraction. Training is a lifelong journey, not a one-time event.

What is a 'fear period' and when do they happen?

Fear periods are developmental windows where a puppy is more sensitive to scary experiences. Common periods occur at 8–10 weeks and again between 6–14 months. During these times, a single bad experience can have a lasting impact. If your puppy is suddenly afraid, don't force them to 'face their fear'. Use treats, create distance, and keep things positive.

Should I use a dominance-based approach for my teenage puppy?

Absolutely not. Dominance and 'alpha' theories have been debunked by modern veterinary science. Using aversive methods like alpha rolls or yelling will only damage your bond and potentially lead to fear-based aggression. At Paws, Claws & Tails, we use evidence-based, fear-free methods that encourage your dog to want to work with you, rather than obeying out of fear.

Keep reading

• Puppy Growth Timeline
• Puppy Development Stages