The legal guardian is the one who can give consent.
No. If your mother has sole legal custody she can consent to your getting married.
No. You need the consent of your legal guardian
Only if the parents are found unfit does the grandparents as well as other relatives have a chance for custody.
In the case of the marriage of a minor, both parents must attend in person and sign their consent if the parents are married. If the parents are not married only one parent has sole custody that parent must attend in person and sign their consent. In the case of joint legal custody both must consent.
Yes, IF you have parental consent (from both parents if they both have custody)
No. And if parents think it's a good idea that their 13yo child gets married they can lose custody.
the person who has physical possesion of the child.
That depends on the state that you live in. There are states that require the consent of both parents if both have custody.
If the mother has legal custody but leaves the state and doesn't have physical custody of your child then that must mean the child is with someone who doesn't have custody. I assume you are not married. In that case, you must establish your paternity in court and request legal and physical custody. If the mother has left the state without taking her child with her the court will certainly want to know who the child is with and will certainly consider awarding legal custody to the other biological parent, you.Perhaps you can convince the mother to consent to your getting legal and physical custody. If not sole custody, then joint legal and physical custody.You should consult with an attorneywho specializes in custody issues. The attorney can review your situation and explain your rights and options.