Changing name of illegitimate child from father to the mother

Hey, y'all.

I have a Filipina girlfriend that has a child. The Child has the fathers last name, she wants to change to her last name instead.

The father left her when the child was 3 years old and the child is 10 years old now, and she hasn't heard of him ever since, for over 7 years now. The father was already married the child is illegitimate. But the father signed the birth certificate and its registered in city hall. And little or no support is given to my girlfriend before and now.

How can i help her to give her advice to change the last name of her child??

I know she need to seek legal advice, and just explain the situation?
Is it possible to change the last name to hers? Even if he signed the birth certificate and acknowledges he is the father? Will be the biggest drama ever even to find him and have contact for her after all these years?

Im Sorry if anything is unclear i will answer gladly any questions , tnx

Joe.

marry her and both of you adopt the child- i would say that's the best option because you can ask the court for the child's name to be changed to yours.

or she adopts her child and does the same.

Allright!

Thank you for the advice sir attyLLL.