Written contracts and promissory notes have a five year statute of limitations in Florida. You'd need to check with an attorney, but I presume the fact that they were making interest payments continues to affirm the loan so the you're within the statute. I also presume that you retained no security interest in the property, you'll have to sue to get your money. Yes your estate (or heirs) could sue if you die if the loan was still within the limitations.

