Babies are almost definitely still getting enough sleep to grow and develop, despite nightwaking.
The detailed answer:
Sleep is very important for brain development, there is no arguing with that, but the amount of sleep your baby or toddler needs is subject to a massive range. The numbers suggested by sleep charts are averages, which means that children can easily fall either side of these amounts.
The best way to tell whether your child is getting enough sleep is to look at how easily your child wakes up in the morning and whether they are happy and alert throughout most of the day.
Nightwaking can continue well into toddlerhood and still be well within the realms of normal sleep. Remember that children’s circadian rhythms don’t develop to the point of matching those of adults until they are 4-years-old.
Read more here: