Legal Puroses

Good afternoon!

My boyfriend was married a man, they have 3 kids..Bago po naging kami, yung wife nya po is nag-abroad.. Then, yung wife nya po yung naunang kumaliwa habang nasa ibang bansa. One of my Boyfriend's friend in Riyahd send him photos of his wife together with his "kalaguyo".

I am 7 months pregnant now, last week po umuwi po yung si "wife" but hindi nya pa po alam ang tungkol sa amin ng "boyfriend ko/husband nya"..

My question is,
1. Is it possible na ilalagay ko yung name ng boyfriend ko
sa birth cert. as biological father of my soon to be child, but surename ko yung dadalhin ng child namin?"
2. What is the effect if ever na surename ko yung dadalhin ng baby namin but nakalagay yung name ng father sa birth cert ng baby?
3. Is there have a chance na (ma-annul/ma void/he can file legal separation) yung marriage nila? where in fact yung wife nya yung unang nangaliwa sa kanila.

1. oo possible pero possible din na gamitin to as evidence kung kasuhan kayo.
2. wala naman. since illegitimate yung bata, ikaw ang may sole parental authority kaya nasa sayo kung papagamit mo surname nun tatay or hindi.
3. depende po yan sa reason na gagamitin nila kung ano man ipafile nila.