I have a 6 year old Quarter horse who is already trained for western pleasure. He gives me a lot of issues though, he tests my authority. When walking him from the pasture to the barn he'll rear, bite, and even attempt to buck and take off running. When you get on to ride him, he won't move, he'd rather just stand around and do nothing. I've been patient, done a ton of ground work, and nothing is helping. He has no respect for me or anyone that handles him. He comes from a great family line, and recently his sire went to Wicked Equine and was trained and sold. His dam is a 4h horse. He was babied at his last home and I think that's where he picked up a lot of these habits. I don't know what to do anymore and I really don't want to sell him. Any tips would be amazing.