Thank God she's safe DJ. I would've been sick. I know you are asking about a bell, but I don't understand why not the GPS device. Other's mentioned a leash. Maybe one that is retractable and attaches to your waist. I know they are a hassle but it's for their protection. We keep leashes on our dogs. My little Maltese would disappear in a second without it. Once while hiking to hot springs beyond Boiling Springs, we had to hike over ledges. My thought was that if my Maltese slipped, that leash would be her life line, literally. My fear would be that one of my three take off after something they see and never come back. That nightmare was almost realized with you, but you were both very fortunate.