unmarried children older than 21

I'm a permanent residency and plan to bring my unmarried daughter who is older than 21 to the US. I was wondering what if any document is required to prove that she is not married?

I'm a permanent residency and plan to bring my unmarried daughter who is older than 21 to the US. I was wondering what if any document is required to prove that she is not married?

There is no specific proof which you can provide that she is not married. You should just fill I-130 and sponsor her.
Good luck.

There is no specific proof which you can provide that she is not married. You should just fill I-130 and sponsor her.
Good luck.

just read the directions and follow the instructions. there are no specific requirements that they ask when you apply for the petition. if they require a certificate that your child is not married, they will take it upon themselves when the time comes, which could well be a long, long time depending on where your daughter is.