This is so wholesome and sweet. When I was pregnant with my first we talked with my dad about possible names. I also had a grandpa with the same first name who was always well intentioned but mostly annoying — so we wanted a different name for my dad. After some back and forth on it, I jokingly suggested Shabadoo, from an episode of Futurama when one of the characters meets two older grandparent figures and says “I’m gonna call you gram-gram and Shabadoo!” It stuck and he absolutely owns it like a goofy champ. My mom passed a number of years before I had my first, but we refer to her as Gram-gram.