UB is 4.5 years old and loves to play ball-fetch in the house. We have long hallways down both sides of our LR and he'll chase that ball for hours. When I take him outside to play (trying to save the walls - but too late for that ) he won't fetch. He'll run to the ball, but acts like he doesn't know what to do with it. I call him back and he'll come, but leave the ball laying. Any suggestions?