My ex-husband owes my mother money from when he got laid off he asked for a loan from her to help pay our bills. It was verbally understood that he would have to pay back this money when he got a job. Almost a year later he got a job but never paid my mother. We are now going through a divorce and he has been paying my mother back. I have a letter that he signed stating how much he owes her and how much he agreed to pay each month until the amount is paid. It is signed by him but it is not notarized. I would like to know if that letter is legit in court. He has threaten to not pay that amount to pay less can he do that?