George Clooney's 'One Fine Day' Daughter Mae Whitman Congratulates Him on Twins With Epic Throwback Pic

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George Clooney's "OG babykid" is happy to welcome his twins to the family.

The 56-year-old actor's One Fine Day daughter, Mae Whitman, took to Twitter on Tuesday to congratulate her onscreen dad on his "new additions" alongside an adorable throwback pic from the set of the 1996 film.

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"Hey congrats george on our new additions to the family love your OG babykid," Whitman captioned the cute snap.

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While Clooney's onscreen daughter sent her congrats, his real-life father, Nick Clooney, has already Skyped with his grandkids.

In an interview with FOX19 NOW, Nick said he and his wife, Nina, were introduced to Ella and Alexander two hours after Amal Clooney gave birth on Tuesday.

"Amal, who is Super Woman, she is just amazing," Nick said. "The babies are beautiful, of course, she's beautiful. She was telling us last week that she is as big as a house. Of course, for her, that’s a very small house. But, she's great."

See more on the Clooney twins in the video below.