For a couple of years, I worked at a lighting shop. We were the go to place in town for many things, especially lighting parts. You'd be surprised at the hundreds of pieces of hardware and glassware that go into lighting and we carried them all. When a customer asked for a specific piece, we'd bring them back to look at the inventory because two people digging through all those little bins would usually result in a successful find.
One day, an older man came in with his son, Buddy. Buddy was an adult, at least 6' tall and mentally handicapped. He had broke the glass cover on a ceiling fixture and his dad came in with some of the pieces to try and find a match. We all stood in front of a shelving unit that was top to bottom glass covers. The dad said we had to do this fast before Buddy lost control and caused some damage in the store so we searched while the dad said, "C'mon, Buddy, show me how you can clap. That's a good boy. Keep going. Buddy, you're the best clapper ever." Every time Buddy would get distracted for a second his dad would remind him to keep clapping and show these nice ladies what a good clapper you are. "There you go, Buddy, you keep doing it just like that because these ladies love clapping."
We found a close enough match and Buddy and his dad left the store with Buddy clapping all the way to the car parked in front. The way that man loved his son made me cry, and I wondered what would happen to Buddy when his dad wasn't around anymore to encourage him to clap his way through the glass.