Great singer but 100% not Fat's daughter!
That's certainly what the rumor was. A rumor from Etta herself. Maybe wishful thinking? Stolen from an interview linked on her Wikipedia page:
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Dorothy Hawkins (Etta's mother) died this past May. But she outlived the man rumored to be James' father -- the enigmatic pool shark, Minnesota Fats. James met him once, in 1987, when she tracked him to the Heritage Hotel in Nashville and rang his room.
"He says, 'I'll be in the lobby,' " she says, pronouncing lobby as 'laahhhhby.' "He talked like that. 'I'll be in the lobby with one of my dames.' He had a vibe like me. As far as me knowing that's my father? I don't know. But he seemed like he was.
"When he passed, he sent me a beautiful golden watch that hung on his clothes that had his name on it. And he sent me a letter, and told me that he wanted me to write a song about him and stuff, which I never did. But I often thought about that."
James looks down wistfully at her hands. Despite a perfect French manicure, they're large, masculine hands -- just like those of Minnesota Fats. Then her head snaps back up. "Oh! And he gave us a picture - and the picture looked just like Donto, my oldest son. It was just like Donto."
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