"They start out with a personality right off the bat," the two-time Oscar winner, 56, told Entertainment Tonight at the Venice Film Festival on Friday, September 1.
"[Alexander] is a thug already. You saw him," George quipped, turning to his pal Matt Damon. "He's a moose! Literally, he just sits and he eats."
The Suburbicon actor, 46, agreed, "He looks like he could bounce right now, some place in Hollywood," as the director added, "Like, checking IDs on the way into the nursery."
As for Ella? "She's very elegant, and all eyes," George gushed. "She looks like Amal, thank God."
The couple, who tied the knot in Italy in September 2014, welcomed Alexander and Ella on June 6. Unlike many celebrities, they opted for traditional names for the babies rather than flashy monikers.
"We just didn't want to have really dumb names," George told ET. "We figured these kids are going to be looked at a lot and watched and [have their] every move sort of judged, and we wanted them to at least have a break with the names. So we looked for some sort of normal names. We didn't have any great inspiration. It wasn't Alexander the Great and Ella Fitzgerald."
Damon interjected, "Alexander Hamilton," as the new father jokingly confirmed, "It was Alexander Hamilton!"
Now, George is adjusting to fatherhood. "I suppose [the realest moment is] just the minute they came out," he admitted. "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.' Everything changes pretty quickly."
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