On Thursday's episode of "The Ellen DeGeneres Show," the Oscar winner revealed he's got zero tips to share with new dad Clooney. "Two babies at once?! That's horrific," the 47-year-old actor joked.
"Because one cries," said DeGeneres.
"And the other one wakes up," Damon interjected. "And then you start crying."
Damon revealed that Clooney, 56 — who directed him in the new crime comedy "Suburbicon" — has recently run into trouble in the diaper-changing department. "He did confide in me that they went on to solid foods last week, so he's trying to get off diaper duty now. Because that's a whole other level," the star shared.
Damon recalled Clooney months ago boasting about his skills. "He was like, 'Diapers are easy!' And I was like, 'Wait for it,'" he said.
Hasfatherhood changed Clooney at all? DeGeneres wondered.
"It took him into his 50s, but I think he grew up finally," Damon said, laughing.
As for his own brood, Damon said he and wife Luciana were excited about dressing up in Halloween costumes with their three youngest — Isabella, 11, Gia, 9, and Stella, 7. (Their oldest, Alexia, is a teen.)
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Since Stella wanted to wear a devil costume, Luciana agreed to dress as an angel. "They're going to be like a duo," Damon explained. "And then my 9-year-old wanted to be a cop, so she asked if I'd be a robber."
"Like an old-fashioned robber?" asked DeGeneres, miming a funny mask around her eyes.
"Like an old-fashioned robber," said Damon, cracking up. "Like the Hamburglar."
Sounds like the best Halloween ever!