You can take step dad to court for the money. Time is not on your side, find out time restrictions on filing a suite against step dad. I have questions for you, and maybe you can see some answers in the questions. I understand the money was a loan. The loan was given to a step family member, which sounds like you cared for very much. Taking your step dad to court and sueing him for the money owed you, will it tare the family picture apart? Money is hard to come by, but so is family. If you can't ask him about it, and maybe come up with ideals for repay of loan, then small claims court could be the answer, but if you care for this person still, then have a sit down, and talk about it. First rule is never go into buisness with family, or loan money to family. It's a little late for that now. How much is family worth? Without any paperwork on the loan, cashed checks is all you have to prove your case. It sounds like he make good money now, but how long will it take for you to save from his payments the amount loaned? Hope you decide to do the right thing, and good luck whatever avenue you take.

