birth certificate inquiry

My daughter is pregnant she is only 17 yrs old will be turning 18 january next year. she will be giving birth on Nov this year 2011. The guy is also a minor they have the same age. We came into an agreement that they will not get married yet not until that their life is already stable, it's like a sort of accidental pregnancy, the worst part is that the parents of the guys does not recognize or say does not agree for what had happened. Well my wife and i just decided not to file any case or sue the guy because it will just worsen the issue and i dont want my daughter to be exposed to this legal matters for her welfare and future.. My question is when she gave birth can the childs name be under our surname? (since they are not married yet), what shall we do when it comes to the birth certificate of the child? Please do help us for some legal advise regarding this matter. More Power & God Bless ....

Thanks
Aldrich

HELLO THERE IM JOAN, MERON AKO DALAWA NA BIRTH CERTIFICATE SA NSO, GUSTO KO SANA PACANCEL YUN ISA, ANO PO KAYLANGAN KO GAWIN THANK YOU