Your 12 Week Old Baby’s Development And Milestones

12 week old baby
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Your 12 Week Old Baby’s Development & Growth Milestones

These past three months have flown by, and your 12 week old baby is getting more active (and more adorable!) every day. Now when you hold her upright, you should see little to no head-wobbling, which means your little one’s neck muscles are getting stronger. If you see that her head is still a little unsteady, concentrate on giving her plenty of “tummy time” on a blanket or play mat on the floor, which will help develop those stabilizing neck and shoulder muscles. Per the Mayo Clinic, give your bean tummy time two or three times a day for 3 to 5 minutes each time. With your support, she may also be able to rest her weight on her legs and make little bouncing movements, practicing for those first steps.

Rolling over is going to become a reality any minute now, which means being extra-vigilant about where you leave your baby while you’re taking a pee/feeding the dog/reading all the articles on Scary Mommy. Even if she’s napping, make sure it’s in a secure spot, because the big roll-over could literally happen any time.

Speaking of sleeping, your tot should still be getting around 14 to 17 hours of sleep, broken up into 3 to 4 hour naps. Unfortunately, even though your baby is sleeping longer and longer, you’re still bleary-eyed and exhausted all day long.

Your 12 Week Old Baby’s Physical, Social, And Cognitive Milestones

She’s also starting to smile and show excitement – maybe even holding out her arms – when she sees people she recognizes and likes. (See? ADORABLE.) This is a thrilling, heart-melting experience for parents, but it can also make for a little bit of awkwardness when baby straight-up rejects someone. Keep in mind that just because you have a lifetime of awesome memories with Aunt Fran doesn’t mean your baby does – to her, she’s still a stranger, a new person to get accustomed to. And who wants to be smothered in kisses from a stranger? Give baby a little time to warm up to anyone unfamiliar, and don’t force her to go to a person she isn’t sure about. Some babies are less social than others (and some will retain their shyness far into childhood). It may help to introduce new people in a familiar setting.

Among all the daily interesting things in your baby’s life, she may also be finding her hands and fingers extra intriguing. Not only is she spending a lot of time staring at her hands in front of her eyes, but she’s also doing a healthy amount of snacking on her fists. Don’t be surprised if your baby sprouts a tooth in a few months as most babies cut their first tooth between 6 to 12 months of age.

By three months, most babies develop a firm grip that they use to clutch rattles, lightweight toys, your hair, your nose, and — somehow — your eyelids. Your little one might also imitate your expressions and movements, recognizes you and close caretakers from further across the room, and gets this hand-eye coordination thing down. Things. Are. Happening.

Your 12 Week Old Baby’s Health

In just a few weeks, your little one will go in for her 4 month well visit where she’ll get her next round of shots, have her weight, length, and head circumference measured. This is the perfect time to speak with the pediatrician about your baby’s milestones, development, and any other questions you may have.

Below, the list of vaccines your 16-week old baby is scheduled for next and what If you want to read up on what vaccines are scheduled next, and the disease they prevent, per the CDC.

This article was originally published in 2015. 

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