The 19 year old said "body-shaming is real" after Garcelle criticized Lisa for posting dance videos online.
Commenting on a video of herself dancing - posted on mom Lisa's Instagram page - Amelia wrote: "My question is why would your dancing videos make me “feel bad”????
"Who was she trying to body shame?? Am I fat? Why would that make me sad????? Body shaming is real. And not okay.
"You can call my mom too skinny or me too skinny but if we called you too big???? Hunny it’s the same thing."
Lisa, 57, captioned the post: "I’d say she’s #Thriving @ameliagray 😀😍😘 #MotherOfTheYear".
Amelia's comment comes after Garcelle made a comment about Lisa's videos on The Real Housewives of Beverly Hills earlier this month.
She said: “I love that Lisa’s free enough to do the videos and be dancing, but the dancing nearly naked is not a choice for me if I had a daughter that had body issues."
Lisa later responded to Garcelle's comments and said "I actually don’t think that is what caused Amelia’s anorexia", adding that she was "so proud" of her daughter for opening up about her struggle with the eating disorder.
Meanwhile, Garcelle has said she hopes Denise Richards doesn't quit the Bravo reality series, amid the Brandi Glanville affair rumors.
She claimed would also not return next season if Denise wasn't by her side.
Garcelle discussed her debut RHOBH season on SiriusXM's EW Live saying: "She's like, 'If you don't come back, I'm not coming back,' and I'm like, 'and if you don't come back, I'm not coming back.'"
She added Lisa Rinna advised her about potential future on the show.
She said: "Rinna said, 'Your first season is always nice and pleasant and the second one they come for you.
"And I said 'Is that a warning?' and she said 'Yes!' So I'm a little scared."
Garcelle also discussed Denise's cease-and-desist order to other castmates over allegations she and Brandi slept together.
The two were apparently together from early 2019 through the middle of last year.
However, the Bravo mom of three has refuted the claims.
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