You sure you're not counting great-uncles as grandpas? Or does your grandma actually keep a harem?
She divorced. Maternal biological grandpa lives in Florida, dunno if they were married. Second grandpa lived with us (well, still does back home.) She's been with Grandpa #3 for like 20 years now. We see them regularly.
Paternal grandpa kicks ass.

He had a SNES which birthed my nintardism.

He never really played it though, his favorites are still Alpha Centauri and Masters of Orion II. Bit of RCT2 in there too.