"It was Alexander Hamilton," Clooney jokingly confirmed.
And while Clooney had been preparing for fatherhood since finding out Amal was pregant last fall, he admitted that the idea that he would be a dad didn't really sink in until they were born in June.
"I suppose [the realest moment is] just the minute they came out," he said of fatherhood. "None of it is real until all of a sudden they're standing there covered in slime and crying. You're like, wait a minute, what is that? We were just two and now we're four."
