I have 5 horses at my barn and 4 of which belong to my dad and myself. The other one belongs to a friend of ours. My horse and our friends horses have become "friends", but mine is having leg issues and isn't being turned out. Whenever out friends horse is out on his own he marches back and forth up and down the fence lines. My dad felt bad for him yesterday and brought him back in the barn. I told him the horse isn't going to stop pacing the next time he is turned out if you keep giving him what he wants. Any advice on how to fix this issue?