Not really co'z obviously the kids father is not supporting him and if you can prove that they have been separated for ages ago so, that will be ok i guess,the father can't do any objection to that unless he is supporting he's kid or have an open communication with him so there's no prolem with that.....but,if he has then i guess you need a consent from him that's all.
btw,in the philippines family law, you can use now the father,s surname even if your'e not married.hope it helps
