infidelity

Good day. I would like to seek advice on my issue. My husband and I are married for 20 yrs. He works in Dubai since 2003. It was only last Jan 2017 that I learned that he has another family in Dubai. He has 2 children ages 12 and 8 now. I don't know what they did to secure a marrige certificate knowing the strict rules in the UAE. I have checked with NSO but there's no registered marriage of my husband and his mistress. I got to see the birth certificate of their daugther, she's registered as legitimate child. The date of marriage of my husband and his mistress on the child's certificate was year 2004 here in the Philippines. That could not be true because my husband was in Dubai that time. They might have used a fake marriage certificate. I want to file a case against them. What is the best thing that you could advice to me please? I really want both of them to pay for their sins. By the way, my husband is still in Dubai, her mistress and the children are noq in the country.
Thank you.

you can try charging them with falsification of public documents on the basis that they reported they were married. They would have had to file a report of live birth in dubai and that would make them liable under PH law

Thank you Attorney for your reply. Can I also file concubinage or VAWC?