9 Month Old Baby Development

Learn everything you need to know about your 9 month old baby. Track important developments and milestones such as talking, walking, growth, memory & more.

Published on June 14, 2017

Young family in livingroom — Photo: Getty

Your Growing Baby

Your Little Mover

In his ninth month, your baby's in constant motion, probably either crawling, pulling to stand, cruising, or perhaps taking his first few toddling steps. Physically he's a go-go kind of kid, but he also has a short attention span. Sure, your baby's interested in almost everything—examining a bug in the grass, flinging toys to the ground, banging blocks together just to hear how they sound—but he won't stay absorbed in one thing for long before flitting off to the next activity. Developmentally, that's totally normal, though you can expect to see his attention span increase to 10 or 15 minutes over the next few months.

Chatty Baby

Whether your baby is saying much, he's certainly learning to communicate, by shaking his head no, for instance, trying to imitate words he hears, and following simple instructions—or refusing to with an impish grin. Believe it or not, the stubborn streak is actually key to his development. When he tosses his cooked carrots overboard or ignores you completely, he's developing his sense of himself as a person who's separate from you. Plus, continuing on his path of destruction, despite your protests, is actually a step toward a prolonged ability to concentrate (though you should be consistent about setting limits, especially where safety issues are concerned).

Of course, in some ways he's still your little baby, a fact you'll be reminded of when he wails as you leave for work or hides his face from interested strangers. As much as he loves testing your limits and showing off his skills, he still craves a good cuddle too.

Health and Safety Info

Time for a Baby Well-Visit

Nine months brings another well-baby visit and another chance to ask about health problems that have been bothering Baby lately. Ear infections, for instance, are the bane of some unlucky babies. If yours has seen a doctor for earaches five or more times in the past few months, ask your pediatrician about long-term solutions to the problem, such as minor surgery to insert ear tubes. Bring up concerns about sleep issues as well, since the flurry of physical activity around 9 months can nix any good sleep patterns your baby's developed. Your pediatrician might be able to offer a few smart tips for dealing with nighttime waking and interrupted naps.

Ready for a New Car Seat?

Now is also a good time to take a fresh look at your baby's car seat. You might have started him out in an infant car seat carrier—perfect for hauling Baby in and out of grocery stores and the day care center without unbuckling him (or even waking him up). But once his feet start to push past the bottom edge of the car seat, or his weight soars over 20 pounds, he's outgrown his cushy digs and needs a convertible car seat instead. The larger seat can accommodate kids up to preschool age (check your car-seat manufacturer's recommendations for specific height and weight limits), but for now, keep it rear-facing. That's safest for babies until they're a year old and weigh at least 20 pounds.

Must-Knows

Ready for a New Routine?

For months, your little guy has been a fan of repetition, wanting to hear the same nursery rhymes, read the same board books, and play the same tickling games over and over again. And no wonder, since repetition strengthens your baby's brain and helps him develop the comforting ability to predict what's going to happen next. Now that he's a little older and wilder, however, he might be ready to break out of his rut, so try introducing a few new toys and books, rotating them in and out every few weeks so there's always something exciting to try his hand at. By the time his shape sorter makes its next appearance, he might figure it out in record time.

The other person ready for a change? You. Sure, routine is comforting to moms as well, but mixing it up will keep the days fresh for both of you. Some ideas:

Try a new route home from work or the grocery store. Studies show it boosts mental quickness and memory (which can be in short supply post-motherhood).
Read something fresh. No time for books? Download an audiobook (your library might offer them for free on its Website) to your MP3 player and listen while baby naps.
Spice up your workout. Want to strengthen your core to prevent back injuries? Try a mother-baby yoga workout DVD, or invest in a jogging stroller and take a few laps around the park. Your baby will love the change of scenery, and so will you.