Dd (13 years old) has her dad's surname
She's been no contact with him for 2 years and wants to change her surname to mine
He has no PR because he couldn't be bothered applying for it but he has for dd2 who also has his surname
I'd prefer her to wait until she's older but she doesn't want her current name on her GCSE certificates etc
If I tell school that she wants to be known as my name will they do that or do they have to use her legal name?