And Pearl the border collie could have been trained to fetch things for the BIL.
Pearl was one of the smartest and most protective dogs I've ever met. Right before my sister's wedding, it so happened I ended up at her parents-in-law's house, while the adults were all out running errands. As he left, my BIL's father said, 'Take care of the place, Pearl.' Every time I opened a door, Pearl was right there by my side, heeling. She hadn't met me prior to that day, but she'd learned that fast that she should protect me as a member of the family. But I would never try to go on their property if the whole family was gone. Once my sister and BIL went away for the weekend, and had a good friend who lived nearby come to feed their livestock. They locked Pearl in the garage. When they got back, the neighbor's truck was in their driveway and Pearl was out. She had heard the neighbor outside, and worked on a crack in the fiberglass garage door until she broke out a big enough hole for her to get through. She broke out, and when the neighbor came back for the next feeding, she charged him. Pearl didn't give him a chance to get back in his truck... she chased him all the way down the road, and as he ran up his own driveway, he was hollering to his wife, 'Open the door! Open the door!' He got in just in time, but he didn't dare go back to get his truck!