Creating account for son. My birthday or his?

I want to create a second account under my name(this is what I’ve read) for my son(7) to use. I plan on setting up parental controls on this for his use cases. The way I understand it is that when he comes of age, we can contact Blizzard, and have the account transferred into his name after providing identification for both of us.

While I’ve read that I have to use my name, I’m just assuming I should be using my birthday. Does/can Blizzard change the birthday on the account along with the name following a transfer to a child?