You forgot to thank some people, Casey Affleck!

During his Oscars Best Actor acceptance speech for Manchester by the Sea on Sunday, Feb. 26, the A-list actor seemed to give a shoutout to everyone in his life, minus a few very special people.

"I didn't thank my children, which is something that I'll probably never ever live down," Casey, 41, told reporters backstage, according to E! News. The star is a dad to two sons, Indiana, 12, and Atticus, 9, with his ex-wife, Summer Phoenix.

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Casey during his Oscars acceptance speech.

"About three seconds after I made it backstage, my phone rang and my son said, 'You didn't even mention us.' And my heart just sank. So, you know, that probably would have been the most meaningful thing I could have said and I failed," he sadly added. The fail to mention came as a surprise to fans, considering in the film he played a troubled man who loses his three children in a house fire.

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Casey even decided to thank his big brother, Ben Affleck, this time around! "Ben I love you," he said onstage, shortly after the two hugged and kissed in the audience after Casey's name was announced as the winner. After the Golden Globes in early January, Casey made headlines after failing to mention Ben in his Best Actor speech, which he also won for Manchester by the Sea.

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Casey and Ben hugging before his acceptance speech.

"I was sort of just curious as to what I was supposed to be thanking him for," Casey told E! News' Giuliana Rancic. "Maybe he thought he was involved in the movie, but he wasn't. There's a lot of things to thank Ben for, but standing at the Golden Globes was not the moment to do it since he wasn't involved in the movie." So, since he won an award for the same film last night, was his shoutout to Ben just because he felt bad from last time?

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However, while backstage after the Oscars last night, Casey quipped, "I mean, not to brag or anything, but I think we're the only two brothers to win Academy Awards, ever." Too cute!

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