From 1990 to 1997 I loaned my sister approx $60k for college and law school with the understanding that she would pay me back when she entered the workforce. She did pay back about $15k but now denies oweing me anything. How can I sue her and are there time limits? I have credit card statements where she initialld her charges but no other real written proof other than a listing of payments she made to me covering the $15k. She live in PA and I live in NJ.