Baby week by week · 3–6 months · 4–5 months: reaching

Your baby at 20 weeks

From Brittany Ryan, Founder and Mom of Two

What’s happening at about 4 months

Five months together! 💛 Your baby is growing stronger, more curious, and more determined to explore the world around them. During playtime, you may notice longer stretches of movement, bigger reactions, and growing excitement when they discover something new. Each wiggle, reach, and push is helping prepare them for the adventures ahead.

What’s ahead

Rolling may be on the horizon. Consider creating safe floor space for movement and introducing larger play mats, activity gyms, or floor mirrors that encourage reaching, turning, and exploration."Little by little, your baby is building the strength to explore their world in new ways." 💛

A memory to keep this week

A favorite mirror reaction

Safety first

Use close adult supervision for every activity. For sleep, follow current safe-sleep guidance and use a firm, flat approved surface. Keep small parts, cords, button batteries and magnets out of reach.

In the app this week

Try this together: Tummy Time Play, plus this week's memory prompts, a private journal and your Journey, quick logs for firsts like explored with hands and made a happy squeal. One simple idea at a time, never 47.

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Guided by: CDC milestones + AAP (HealthyChildren.org) + CPSC, written in Brittany's words.

Every pregnancy and every baby is different. This is general, educational information, not medical advice. If something worries you, check with your provider or pediatrician.

Meet our founder

Brittany Ryan

Founder and Mom of Two

Brittany is a mom of two with a background in early childhood development. Little by Little Together began with a beautiful, blank baby book. Like so many parents, she bought baby books with every intention of filling them; instead, they sat in a closet while life kept moving. So she built a personal assistant for parenthood that tells you what matters right now, offers one simple idea at a time, and keeps your story safe.

“You don’t have to remember everything at once. Little by little, there is a story worth keeping.”

Read Brittany's story

Founding 500 · applications open until Mother's Day 2027

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