Child Development Deep Dive: Early Childhood (2-5 year olds)

Why the First Years Are a Race Against the Clock

Kelly Brzak opened with a clock. If you get to serve a child of three or younger, you are racing it. The whole child grows faster in these years than at any later point in life. She also named a real access problem. Some states will not honor a diagnosis or fund services before age four. That access gap means some BCBAs (board certified behavior analysts) may never work with a child this young. Brzak has worked with two-year-olds herself.

Little kids depend on adults for food, shelter, clothing, and nearly everything else. What happens now tends to echo for years. She pointed to research on children raised in Eastern European orphanages. The earlier an infant leaves a deprived setting, the more ground that child makes up. So she asks teams to weigh four things at once. Emotional safety, physical safety, thinking skills, and the right dose of stimulation all matter together.

The classic window runs from birth to four. Brzak stretched hers to five. After COVID, she said, many people agree that milestones look a bit different now. Bodies are working hard in this stretch too. She cited Burke: small children need about twice the calories per body mass that adults need. Growth this fast is why every session carries weight.

Every single minute that you're with a kid this age is an opportunity to connect and share.

From the talk — Kelly Brzak

Safety Is a Clinical Decision, Not a Side Note

Two to five year olds move. They climb, run, spin, jump, crawl, and dance. They also see far less of the room than you do. Depth perception and object permanence (knowing things exist when hidden) are still coming in. So hand holding, close proximity, and help in and out of the car are part of the job.

Brzak means safety in three ways: physical, psychological, and emotional. She also draws clear lines around touch. A side hug works. A child parked in your lap or your technician's lap does not. She says no thank you when a child tries to kiss her. The point is not coldness. The point is that we should not teach young kids to be very friendly with strangers.

Two more safety habits came up. You are a mandated reporter (required by law to report concerns), and small children cannot advocate for themselves. Make the call and let others sort out whether it holds. Refer out when the need sits outside your training. Severe feeding problems were her example. ABA can support feeding work, but not every analyst has that depth. She added one warning from experience: scarves, necklaces, and glasses get grabbed, so leave them home.

The environment needs to be safe.

From the talk — Kelly Brzak

What 2 to 5 Development Actually Looks Like

Emotional signs show up early: smiling, orienting toward a caregiver, hugging, touching, laughing, and crying when something is wrong. Frustration shows up too, and so do the first attempts to solve a problem. Brzak wants teams to watch the whole child, not only the boxes on the protocol.

Language grows on adult responses and adult examples. Even tiny babies pause and orient when someone speaks to them. A babbling baby will take turns with you if you stay quiet long enough. That pause is the lesson. Speaker and responder roles get practiced long before real words arrive.

Social play in this range is often parallel play (playing beside, not with). Imitation repertoires (copying what adults do) start here too, and that cuts both ways. Brzak's own toddler repeated a swear word she let slip. Children also imprint on a favored caregiver and check in constantly. Younger kids follow older kids, so a sibling in the room can pull more responding out of your client.

These little people can go through the whole gamut of emotions.

From the talk — Kelly Brzak

Get More Out of the VB-MAPP Than the Milestones Page

The VB-MAPP (a language milestones assessment) is loved or hated. It maps typical milestones for birth to four: vocal, social, and visual perceptual skills, with pre academic skills at level three. Brzak reads the milestones grid as a brick wall. Every rectangle you fill before age five strengthens the child's communication foundation. Even if you dislike the tool, she asks you to run it once for a young child. Scan for gaps.

The tool has three parts, and two of them get skipped. The barriers assessment (a scan for learning roadblocks) can be walked through with a caregiver. It shows you which barriers to attack first for this one child. The transitions assessment (the third part of that tool) is worth opening before you move on to other tools.

She also uses the Essential 8 booklet from Essentials for Living with every child on her caseload. It has a running record style (an ongoing log across targets). That covers leisure activities, requests, and tolerating a denied or delayed request. Some insurers accept it as an assessment tool. Her bigger push: stop reassessing only every six months. Keep the tool in your bag and look at it often.

Really, our assessment tools are supposed to help us scaffold the learning for the child.

From the talk — Kelly Brzak

The Word Gap Is a Reason to Talk More

Brzak walked through data from Meaningful Differences in the Everyday Experience of Young American Children. The study followed 42 families across income groups: 13 professional, 10 middle, 13 lower, and 3 welfare families. SES here means family income and education level.

The kids started talking at about the same age no matter the group. The size of their vocabulary was another story. By age three, children in professional families had about 1,100 words. Children in welfare families had about 500. By that same age, one group had heard about 30 million words and the other about 10 million. The work reported a strong link between vocabulary and IQ.

Her takeaway is practical. If you serve a young child in a home with spare resources, bring the extra. Bring extra language, extra playtime, and extra energy into that room. You are one of the adults who can close part of that gap.

If you look at the bottom, the children started talking at approximately the same time, despite their SES considerations.

From the talk — Kelly Brzak

Write Goals That Let a Small Child Win

Brzak spends real time on trials to criterion (how many correct tries equal mastery). Her goals for this age look small on purpose. A child expressively identifies three of three items per session across six sessions. A child imitates two of two actions. She admits she was trained to think eight of ten sounded stronger. What she got when she pushed past two or three was task refusal and elopement (running off from the session).

Do the math on a common goal. Eight of ten colors across five sessions asks a child to tact (name something they see) 50 times. Unless you brought an artist's set of markers, the same colors come around again and again. That is hoop jumping. Rewrite it as two of two colors across eight total colors. Two and three year olds may also not be ready to sort colors at all, so play beats trials there.

Two more rewrites came up. She crosses the word seated out of goals and asks why it was there in the first place. Shape attention through 15, 30, 45, then 60 seconds, and celebrate five seconds if that is what you get. Then drop zero instances of maladaptive behavior (behavior that gets in the way) as a target. Her small caregiver survey said daily crying and tantrums are the norm. Try self soothing or accepting redirection within 30 seconds instead.

These are all age appropriate and common behaviors.

From the talk — Kelly Brzak

Play, Repetition, and a Longer Wait

Her teaching rules are short. Bring play. Use repetition. Watch how much language you pile on. She codes technician language on a sheet so the team can see its own habits. Every extra question is one more chance for a child to avoid you or say no. Say car, beep beep. Skip the stack of who, what, and where questions.

Wait longer than feels normal. Instead of a three to five second window, she gives a long silence before prompting again. That longer latency (the pause before you prompt) is where many kids answer on their own. She also reframed the old fight over teaching format. Good NET (teaching inside natural play) is DTT (short structured teaching trials) embedded in the natural environment. Each trial keeps the same parts intact.

Materials matter more than people expect. Bring a variety of play items, sized so nothing is a choking risk and small hands can still manage. Ask the family what they already own. Pack sanitizer, wipes, tissues, band aids, and gloves for the team. Kid sized chairs, tables, and step stools help a child act on their own. Tiny board books with one word and one animal per page let a parent feel successful reading aloud.

One more thing to expect. A child with neurological differences may not smile back or look up at you. That missing feedback can quietly punish your own playing. Notice it happening in yourself, then keep playing anyway.

Reduce demands does not mean reduce learning.

From the talk — Kelly Brzak

Pairing With Caregivers Without Adding Stress

Pairing (building fun before asking for work) starts with your own head. Brzak asks teams to suspend judgment of the family. Clinical expertise is not permission to look down on anyone. Ask how the parent is doing and mean it. Remember who was sick last week and ask about them. Do not take it personally when a family ghosts you, and keep offering times.

Her pairing answer for the child is blunt: bring a bag of stuff. Puzzles, books, stickers, shapes. Something in there will land. Then watch the child's eyes and hands, and narrate what they are already looking at. Be goofy. Imitate favorite characters. A colleague she consulted added that purposeful touch, matched to the child's preferences, matters at this age.

With caregivers, showing beats handing over a printout to sign. Model the skill. Pick one goal area per session and let the parent choose from a few. Include parents in running trials. That means short echoic trials (having the child repeat sounds) and FCT practice (teaching the child to ask). Invite siblings in. Loop in teachers or preschool staff, and offer to come along on an outing.

Set your technicians up the same way. They need to know how to play, spot incidental teaching moments (teaching that happens through everyday activity), and bring energy. Ask directly whether they are comfortable with toileting and other messes. You will find out either way, so it is better to know first.

There is a difference between showing and telling.

From the talk — Kelly Brzak