To be honest if it's not the name, kids would find something else to make fun of, even if it's a stretch. From my surname I got "lend a hand" and I was always like how on any planet is that funny? I also got called "bum feeler" for years because one time I was pushed into somebody and my hand happened to hit somebody's arse so.... I mean, she'd probably get something anyway and Butch
Cassidy isn't a particularly bad one. At least it won't make her out as an 8-year-old sexual deviant lmfao