It's a bit sappy, yes. But aren't most mother/son dances?
Go for it if you like it!
I have no idea what the boy is going to pick for his mother/son dance. I asked and he didn't seem to be concerned about it.
Should my brother ever get married, I'm callin' it right now...he and my mom will be dancing to either "In My Life" by The Beatles or "Beautiful Boy" by John Lennon.