Regardless of state, I am very confident you have no statute of limitations problem. Send a demand letter for the money immediately and state that the debtor has a certain amount of time to pay the money, with interest, or you will sue in court.
My guess is that you didn't give this loan pursuant to a properly drafted written note with creditor protections -- I hope not but this is frequently the case with relatives, where the trust factor is high. You might be able to put a lien on the house with the judgment. I would file suit if you don't receive the payment, obtain a judgment, and file...
Speak to the clerk at the county courthouse or, better yet, to a lawyer since you will need to go to a higher court than Small Claims or even Civil Court. The amount in controversy is high...