Petition for Mother

[jay-bee 0]

I am about to file an I-130 for my mother who is in the Philippines. She has been using my father's last name but they are not legally married. Her current and previous passports, voter's id, bank account, etc are using my father's last name. Back in the old days, she had a marriage certificate obtained from a local city hall but was never registered in the national database. My father is legally married to someone else. I am using my father's last name too.

So, my question is, when I filed a petition, should I file it using her 'maiden' name? or if use her 'married' name, is it required to submit an authenticated marriage certificate when filing either I-130 or I-485?

Thank you!