Bakit hindi pinangalan in the 1st place ang bata sa father? Kahit hindi pa kasal eh puede naman ipangalan, kahit nga illegitimate basta the father ACCEPTS paternity of the child. Tapos, another "negligent oversight" -- bakit hindi nagawa when they got married? Was the father denying paternity from the start?
Anyway, given ganyan ang situation ngayon -- the timing is very complicated na -- get a lawyer to help you with the documentary requirements. Ang bata, KUNG GUSTO ng mother, has the LEGAL RIGHT to use the father's surname. Quesehoda illegitimate, natural or legimate child yan -- it has the right to the father's surname.
Now, ibang usapan yan kung ang father ayaw umamin sya ang father ng bata. Denial of paternity requires a more complicated legal answer. May legal procedure required to prove paternity and to file a case in court to force the father to acknowledge paternity. Get a competent lawyer for this, get a lawyer you trust lalo na kung ang father eh mapera or nakapuesto or influential. Malaking laban yan, and you will need a lawyer na hindi kayang takutin or bilhin ng reluctant father.
A case against the reluctant father eh magastos. Pero isipin din ng mother, kung talagang SIGURADO sya about the child's paternity -- eh go for it. Pagnanalo sa case -- the kid gets to use the surname of the father AND (eto importante) gets the RIGHT TO INHERIT. Also, pag nag file ng case eh automatic hinihingi ang lawyer for the mother - reimbursement of legal expenses, damages for sleepless nights, anguish etc etc maisaksak pa ng lawyer na magaling. And so pagnanalo, hindi lang reimbursed si mother, baka kumita pa si mother sa pagkakapanalo ng kaso.
Basta tandaan mga Sis, whatever the situation -- basta cooperative ang father, there is no hadlang to the kid using the father's surname. Kahit ilan pa ang asawa ng father -- the child has the right to the surname. Pero, kahit single ang father, pero ayaw umamin sya ang father -- yan ma-delay lang but eventually, pag na prove ang paternity -- the child will use the father's surname.