Yes — Grandpa Charlie is really happening after the actor announced the "fabulous" news that his 28-year-old daughter Cassandra Estevez is expecting her first baby.
"Me as a grandfather, Dave… I don't know," he told David Letterman on his late night show on Monday.
"It's like the world's going to crack in half. Its fabulous. It's just not a title I'm ready to adopt."
Charlie quipped that he'll be a good grandparent because "you can leave the kid."
Cassandra is the product of Charlie's relationship with his high school girlfriend Paula Profit when he was 19-years-old.
The Anger Management star also has two daughters with second wife Denise Richards; Sam, eight, and Lola, seven. And he has three-year-old twins, Bob and Max, with third wife Brooke Mueller.
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