Pregnancy week by week · Second trimester

21 weeks pregnant: what's happening

From Brittany Ryan, Founder and Mom of Two

Your baby's movements may be becoming part of your daily rhythm. Eyebrows and eyelids are formed, and swallowing practice continues. What once felt like occasional flutters may now be becoming a familiar part of your day.

What's ahead

Your baby's senses will become increasingly active in the coming weeks. You may notice stronger movements and begin wondering which voices, sounds, and routines already feel familiar to them.

A memory to keep this week

A movement pattern you are beginning to recognize

Write it down while it's fresh. In the app, each week has gentle prompts like this one, saved privately to your story.

In the app this week

Try this together: Start Baby's Library, plus this week's memory prompts, a private journal and your Journey. One simple idea at a time, never 47.

Become a Founding Mom Join the launch list

Based on: NHS week-by-week guide to pregnancy, 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

Help shape the app as a founding mom

Open to moms and expecting moms across the US. Brittany reads every application; selected founding moms get Plus access. Fields marked * are required.

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I’m 18 or older, I’m a mom or expecting mom, and I live in the US. * I agree to the Founding 500 application terms (Draft, pending legal review), including Plus access for five years if selected. * I give Little by Little Together permission to use the introduction and other content I choose to submit to the Founding 500 program, with my first name, for app improvement and marketing. This includes publishing, editing for length without changing my meaning, and distribution across the brand’s website, social channels and app materials. Monthly check-ins are optional. This permission does not include my private in-app memories. * Send me launch news and sneak peeks. I can unsubscribe anytime. (Optional)

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