I am looking for a new bat fro my daughter and not sure on length/weight...she will be 12 in a few months, is 5ft 5inches tall and weighs 145lbs, has played several years of Little League but now moving on to U12 Travel team. Last year she used a 31" 19oz. bat and hit the ball well with many doubles and triples, she is strong and I am wondering how much to move up in bat size...any recommendations?