Sidibe, the star of "Precious: Based on the Novel 'Push' By Sapphire," lost the best actress Oscar to Sandra Bullock Sunday night.
Stern later predicted on his Sirius Radio show that Sidibe's weight would prevent her from having a long career in Hollywood.
But Alice Tan Ridley, Sidibe's mother, told TV's "Inside Edition" she doesn't think Stern is correct.
"He can see, you can see, I can see Gabby is a big girl. She's a big woman, so what's wrong with that? She's not like everyone else in the world," Ridley said. "I don't see him giving jobs out to anybody so why should we care what he says? He might not hire her, but someone else will."
Ridley went on to say her daughter will keep her head held high despite what anyone may say about her.
"You're going to be who you are no matter what anyone has to say about it," Ridley told "Inside Edition." "They didn't make you, don't let them break you."
Since making "Precious," Sidibe has filmed a second movie and is working on a new Showtime series called "The C Word," starring Laura Linney.