It is very common for many children to start off with blonde hair who are not going to be natural blondes as adults. I always wondered why that was and what the evolutionary reason was for it. I still wonder why it is an evolutionary trait. Do parents treat blonde children better with more care? I don’t know.
Babies of all races have less melanin, this is because they need yo absorb more vitamin D.
As we age we need it less, hence the darkening hair