Yeah until she's 18 you need his permission. I started using my step fathers surname in primary school and all my school records were in that name but it wasn't my legal name. Had to get real father to sign a form agreeing to me changing it legally when I realized it was going to be difficult to apply for uni in legal name and have no school records! He was not happy about it but he did it.

Interestingly we have been completely estranged for about 13 years now.