Now he isnt some big, bulky boy. My guess is that he hands 13 hands IF that. Late bloomer, straggly and imho still looks like a yearling. No matter what I tell them they don't believe that breaking him to ride would create issues. Now if he was solid and not such a little guy I would let them do as they please. However, this bothers me. Does anyone have any information on the dangers of starting horses too early? I know if they see actual information about the dangers of it they will rethink this. They do love him, just arent trainers.