Ex Husband bringing Lawsuit against my Parents?!?!

My ex husband and his parents are suing my parents over $13,000 that was given to my parents when we were first married. It is a complicated situation, but here is a summary. "Tim", my ex husband, had a secured loan that he obtained before we were married, the loan was secured by his parents at a local bank. The money was origianlly used to purchace a mobile home. "Tim" and I got married in 1995 and my parents being the generous people they are decided to build another home and let us live there rent free. "Tim" sold the trailer and offered to give the $13000 to my father to help out on the house. Because the loan was secured by "tim's" parents they asked my dad to sign a statement saying that in the event of divorce or death my dad would repay the money. He did sign an informal statement agreeing to this. "Tim" gave the money to my dad and we continued to pay on the original secured loan at the bank. Well now is is 5 years later and I have divorced "Tim" due to spousal abuse and he and his parents are suing my parents for the $13000 and a share of the house. For the past 5 years my parents didn't charge us any rent or taxes on the house and basically supported us for several of those years. They purchaced all of our groceries and provided much financial support including loaning "Tim" $5000 to purchace a truck. The reamining balance on the original secured loan is $7600. My father offered to pay Tim the $7600 minus the $5000 owed to him on the truck. Are my parents responsible to pay back the full $13000 and do they have any right to attach to the house even though it is and always has been in my dad's name only. Any help you could provide would be greatly appreciated.

If your dad signed a statement (formal or informal) agreeing to pay back the $13,000 in the event of divorce or death, then he is obligated to repay the $13,000, since the two of you are now divorced. If he has proof that he gave Tim $5,000, your dad should be able to deduct this from the $13,000, which would leave a balance of $8,000. I don't think Tim's parents would be able to make any claims on the house, since it is in your dad's name, unless they are considering the house as collateral and want to put a lein on it to get the money your dad owes them.