Your baby at 4 months old
weighs 6.5kg and is 65cm long on average, can hold him or herself up with a bit of support, lift the head and legs when lying face up, and stretch the legs out when lying face down. Baby will try and grab hold of objects and have fun with objects like rattles. Your baby will babble at the sound of your voice, laugh a lot, turn towards you when you call his or her name and smile at his or her reflection in the mirror. Your baby will become sociable and won't like being left alone for long. Colour vision is almost as sharp as an adult’s at this age.
The fourth month is the time for baby’s next diphtheria, tetanus, pertussis, polio, Haemophilus influenzae
type b and Meningitis C injections, as well as the first vaccination to protect against pneumococcal infections.
At 4 months old, your baby no longer needs feeding in the middle of the night, but may still wake up. A feed will often help get baby back to sleep, even if it's not needed. It may be better to let baby suck his or her thumb instead. In any case, it’s important that baby nods off as happily as possible, so don’t create a fuss, even when your baby cries.
Your baby has babbling and gurgling down to a fine art, babbles to toys and imitates your intonations and accent. Although babies of this age are now aware of their existence, they're not fully aware of the permanent presence of objects when they’re out of their field of vision. To help your baby progress, play games such as alternating showing and hiding your face or an object.