I am not sure that any other animal has evolved to have it's skull and brain squished hard during birth, like we have. This is why chimps outsmart human children for the first years of life. We do indeed have a very unusually plastic brain.

That is interesting. I don't think that you can say that the cause is our brain being squished during birth. I think the child lags behind at first because it has to do deeper learning and hence it takes more time. i.e. The brain is learning a lot more patterns, and patterns within patterns, than the chimp. Remember that a baby is also learning to speak. The child just has a lot more brain cells it needs to train. Although, a child at one year will already understand a lot of what you say, not sure about the chimp.