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Anne Hathaway made a big decision last October, but we're only just now hearing it: She's decided to stop drinking.
And it appears that her son Jonathan, 2, was a big influence on her deciding to go cold turkey for 18 years.
"I'm going to stop drinking while my son is living in my house, just because I don't totally love the way I do it and he's getting to an age where he really does need me all the time in the morning," she revealed on "The Ellen DeGeneres Show" Tuesday.
"I did one school run one day where I dropped him off at school, I wasn't driving, but I was hung over and that was enough for me," Hathaway, 36, added. "I didn't love that one."
"Yeah, that's another reason I don't want kids," joked DeGeneres.
Jonathan's dad is Hathaway's husband Adam Shulman; they've been married since 2012.
But there was another factor that played into the Oscar-winner's resolution: drinking rum with her "Serenity" co-star Matthew McConaughey and his wife Camila Alves while making the thriller, which hits theaters on Friday.
"We drank the night away, and then I had to go to a meeting with Steven Knight, our director, the next day, and I was just kinda — have you guys ever had to do a meeting hung over?" she asked the audience. "I was just kinda stumbling in with one eye open and I was trying to convince him about certain things about my character."
She 'fessed up afterward, and the director said he "couldn't tell" she'd been hung over. "Then, two days later, we had another meeting and I showed up and said, 'Oh, now I can (tell).'"