Tantrums and emotional outbursts are a natural part of child development, but that doesn’t make them any easier for parents to manage. Whether you’re dealing with a toddler’s full-blown meltdown in a grocery store, a defiant preteen, or a moody teenager shutting down, understanding what’s happening behind these behaviors can make a world of difference.
Children act out for a reason—every tantrum and behavioral change can signal something. The challenge for parents is deciphering what their child needs at each developmental stage and responding with patience, understanding, and effective guidance.
This guide walks through major developmental milestones from birth to 18 years old, explaining why kids behave the way they do, what’s normal, and how parents can foster emotional growth through supportive, age-appropriate strategies.
1. Infancy (0-12 Months) – The Foundation of Emotional Development
Key Milestones:
- Developing attachment and trust
- Recognizing familiar faces and voices
- Expressing needs through crying and fussiness
Common Behavior Challenges:
- Crying as communication – Babies cry because they can’t use words yet. Every cry signals something: hunger, discomfort, tiredness, overstimulation, or simply a need for closeness.
- Stranger anxiety – Around 6-9 months, babies begin build a strong preference for their primary caregivers, which can lead to distress when anyone comes closer to the baby than their primary caregiver. This is a healthy but challenging phase, as even neighbors and family members who are not around the baby a few times a week (grandparents, aunt, uncles, cousins etc.) will not be seen by the baby as part of the “inner circle”. This does not mean the baby does not like a person, it is just a phase.
- Tip: If a baby is in their Stranger Anxiety phase, try ignoring the baby for 5 minutes when you first see them. Avoid eye contact and speaking directly speaking to or touching the baby, and put your focus on warm, friendly interaction with the parent. This will allow the baby to check you out and see that their parent trusts you.
- Frustration from limited mobility and communication – As babies become more curious about their environment, they get frustrated when they can’t reach objects or express their needs
How to Support Your Baby:
- Respond with consistency – Babies have no idea what is OK and what is not, so they try everything. All children depend on their parents to set consistent boundaries, and firmly but gently correct behaviors that aren’t OK. As parental guidance leads to little successes socially and behaviorally, babies build good habits, and these little successes begin adding up to big successes. This pattern crowds out unwanted behaviors over time and builds a foundation for emotional security.
- Use consistent routines – Predictability helps babies understand daily life and establish routines for sleep, feeding, and playtime.
- Encourage early communication – Use gestures, facial expressions, and body language to help babies express themselves before they can speak.
- Put your phone away – Screen use by parents while babies and toddlers are with a parent stunts communication and social development. If your attention is on your phone, you aren’t showing gestures, facial expressions and body language to your baby. Avoid using a screen to entertain your baby if they are fussy. This teaches them to entertain themselves and ignore their needs, instead of working out their problems and developing creativity.
2. Toddlerhood (1-3 Years) – The Age of Tantrums
Key Milestones:
- Learning independence (“I do it myself!”)
- Developing language skills
- Experiencing big emotions with limited skills in handling them
Common Behavior Challenges:
- Frequent tantrums – Toddlers have big feelings but little control over them. When they’re frustrated, hungry, tired, or overstimulated, tantrums often become their go-to response.
- Power struggles – The desire for control is strong at this age, leading to constant battles over food, clothing, and bedtime. This is a battle that should consistently be won by parents, though choosing your battles can be a strategy that helps children and parents through a difficult stage of development.
- Separation anxiety – Many toddlers go through phases of needing extra reassurance, especially during drop offs.
- Tip: It is only the act of being separated that upsets the child in this phase. Make goodbye’s short and consistent. The longer you drag out the separation, the more the child’s agitation will escalate.
How to Support Your Toddler:
- Set clear, consistent boundaries – Toddlers thrive on knowing what to expect. Be firm but loving.
- Offer choices – Instead of saying, “Put on your shoes,” try, “Do you want to wear the red shoes or the blue ones?” This gives them a sense of control.
- Use redirection – If they throw a toy, instead of scolding, guide them to an appropriate action: “Toys stay on the ground. Let’s throw this ball outside instead!”
- Help them name emotions – Saying, “You’re feeling really mad because you wanted more cookies” teaches them to understand and express their emotions.
3. Preschool Years (3-5 Years) – Big Imagination, Big Feelings
Key Milestones:
- Expanding language and social skills
- Increased independence and curiosity
- Beginning to understand rules and limits
Common Behavior Challenges:
- Meltdowns over small things – Expression advances far faster than emotional regulation at this age, so even small disappointments (like getting the wrong color cup) can lead to large emotional expressions.
- Testing boundaries – Preschoolers push limits to learn what is acceptable and what is not. They also want to find out how much they can get of what they want.
- Struggles with sharing & peer interactions – Learning to take turns and share is a process that takes time. This is an age where social interests are far beyond social skills for most children.
How to Support Your Preschooler:
- Give Emotional Guidance – To a toddler, the approval of a parent is gold. If throwing a fit or tantrum gets your attention the best, they will do it more and more often. The secret is to catch them being good! Drop whatever you are doing and give them your full attention when a polite request is made. This shows your toddler that asking for attention the right way pays off. They will quickly learn to repeat polite behavior. If a demanding or whiny request is made, gently direct your child to ask again, the right way. If they do so, meet the request and praise their improvement. If they escalate into a fit or tantrum, completely ignore the behavior and request and simply walk away. This shows your toddler that whining and throwing fits does not work to get your attention. After a couple weeks of this approach, you will see dramatically fewer tantrums and dramatically more use of good manners.
- Model problem-solving – Instead of fixing things for them, guide them: “What do you think we should do if your friend doesn’t want to share the toy?”
- Praise effort, not just outcomes – Encouragement fosters resilience: “I love how you kept trying to tie your shoes!”
4. Early Childhood (6-9 Years) – Emotional Growth & Social Development
Key Milestones:
- Greater emotional regulation
- Beginning to comprehend fairness and rules
- Forming friendships with shared interests
Common Behavior Challenges:
- Mood swings & frustration with failure – Small and steady hormone changes occur that mature the brain and provide a child with better understanding of social rules and a stronger sense of right and wrong. These increased capabilities come with new challenges, often leading to self-doubt when they struggle with a new skill.
- Increased comparison with peers – Friendships become important, and children start comparing themselves to others. Most children at this age feel a strong desire to fit in and prefer to be with children who are the most similar to them.
- Occasional defiance & rule testing – Kids this age want to know how far they can push limits. Their advancing social skills allow them to think ahead when trying to get what they want. This leads to exploring social manipulation and a lot of friend drama!
- Tip– Discourage the use of the term “best friend” and replace it with “good friend”. This will reduce unneeded social competitions and help many people feel included at a stage of life when such inclusion is very important.
How to Support Your Child:
- Encourage growth mindset thinking: “Mistakes help us learn!” and “Practice Makes Perfect!”
- Help them navigate friendships by practicing empathy and social skills.
- Emphasize ownership of mistakes that your child has made. Teaching your child to own their mistakes and apologize in person to someone they have wronged is one of the most valuable skills a child can learn at this age. It is also healing for the friend or parent who was treated poorly. Learning to repair trust is an opportunity both sides benefit from at this stage of development.
5. Preteen Years (10-12 Years) – The Tween Phase
Key Milestones:
- Stronger self-identity and awareness
- Desire for independence but still reliant on parents
- Growing baseline anxiety
Common Behavior Challenges:
- Further steady hormone development leads to increasing anxiety with limited coping skills
- Peer pressure begins to play a role
How to Support Your Preteen:
- Keep communication open and non-judgmental.
- Give them responsibilities and chores to foster independence. Chores give a child a sense of accomplishment and purpose at this age, a much-needed gift on hard days.
- Set clear expectations around technology, friendships, and behavior, and enforce those expectations. If a tween doesn’t think you care about them breaking rules, they are likely to break many more rules as the teen years arrive. This is the phase of life to teach your child that all choices have consequences, some small, some big, and that it is important to avoid big consequences.
6. Teen Years (13-18 Years) – Developing Maturity and an Independent Worldview
Key Milestones:
- Hormone development becomes less steady, with periods of being overwhelmed
- Developing independence from parents and siblings
- Preparing for adulthood
Common Behavior Challenges:
- Increased risk-taking behavior
- Emotional highs and lows
- Balancing independence with family expectations
How to Support Your Teen:
- Respect their need for privacy while staying involved in their life.
- Help them think through consequences rather than lecturing.
- Support their goals and dreams by being their biggest cheerleader.
Do not shy away from avoiding choices that have irreversible consequences. Drug addiction, pregnancy, infections with no cure such as HIV and herpes, and suicide should all be discussed before a teen faces these realities. It is your responsibility as a parent to bring up these realities and guide your child to steer away from them when they are encountered.
Embrace Each Stage with Pediatric Support
Having children is an incredible blessing, but the task of turning a newborn into a healthy responsible adult who will make the world a better place is an overwhelming task! Every stage of childhood presents new challenges for parents. With patience, understanding, and the right strategies, parents can guide children into emotionally healthy adults. The joy and sense of accomplishment completing this task brings a parent has a depth and meaning unlike anything else in life. The saying “It takes a village to raise a child” is true, and we at Redwood Pediatrics are honored to be a part of your village. Giving medical care, behavioral guidance and cheering on your children as they grow is a privilege we take very seriously. We understand the challenges of parenthood, and in us you have a supportive medical partner giving your child the best knowledge, wisdom and care every step of the way.
Want more parenting support? Call to schedule your child’s first appointment at one of our Kansas City Northland locations! Call today for help with tantrum management and emotional support.
