12 week old baby

Your baby’s development at 12 weeks old

Just as you were getting used to a bit more sleep at night (maybe), your baby is likely to have another growth spurt around now. You’ll know the signs by now: waking more frequently to feed, perhaps wanting food every two hours in the day instead of lasting three to four hours between feeds, and just seeming a bit more restless about life. There’s nothing to do but go with it: if you’re breastfeeding, your milk production will step up within a day or two and you’ll be back on track in no time.

Nap time

By now your baby is probably sleeping 12 hours at night, broken up by around two feeds between their bedtime and getting-up time. They’ll also be taking about three naps in the day of varying lengths. You’ve probably begun to notice a pattern emerging, so introduce a daytime sleep routine that suits both of you. It’s worth doing while they’re little so they get used to the idea of going to bed at certain times during the day. Even if they don’t sleep, it’s a quiet, resting time for their brain and allows you some headspace to get on with other things too.



It sounds a bit back-to-front, but babies and toddlers need regular daytime sleep in order to sleep well at night. If they get over-tired, they’ll actually be harder to settle at night.

Eye health

Your baby’s eyes are really working well together now, tracking moving objects smoothly, and developing better 3D vision and depth perception. Small babies often squint because of the effort it takes to focus, but if your 12-week old is still squinting, it’s important to mention it to your GP. Untreated squints can cause vision problems later that are hard to fix.

Jabs at 12 weeks

It’s about time now for the second batch of immunisations at three months old. Your baby will be getting the second dose of the 6-in-1 injection which protects against diphtheria, tetanus, whooping cough (pertussis), polio, hepatitis B and Hib (haemophilus influenza type B). They’ll also have their second dose of the rotavirus vaccine (a liquid dropped straight into their mouth). These are usually done at the same appointment. If you felt daunted and worried about your first immunisation appointment, you’ll know what to expect this time – and that it isn’t nearly as bad as you feared. If your baby had a slight fever or irritability in the hours after the jabs last time, they may this time too.

Good toys for a 12 week old baby

Your baby will still love their baby gym, black and white books and rattles, but now is a good time to introduce a few other toys: try soft, stacking blocks, electronic toys with simple buttons to press, plus toys with interesting textures such as crinkly, squishy and squeaky (although it will be a few more months until they are able to press a squeaky toy successfully).

Tips from other Bounty mums

"Remember your baby has never been a baby before and you have never been a mummy. You learn together." – Julie