Not sure whether the facts will pan out, could just be a disgruntled Australian throwing barbs. Would be interesting if she felt that she could overcome the prevalent size bias in Hollywood but not age.

http://www.news.com.au/entertainment/books-magazines/high-school-photo-shows-rebel-wilson-is-actually-36/story-fnk84xng-1227359266762

REBEL Wilson has hit back at rumours the Australian actress has lied about her age.
In a series of tweets, Wilson poked fun at the speculation, after a source who went to school with the comedian at Sydney’s Tara Anglican School for Girls in North Parramatta told Woman’s Day magazine that the Pitch Perfect star is not 29.
“ ... No-one knew of a Rebel Wilson,” the source told the magazine.
“Her name is — or was — Melanie Elizabeth Bownds, and she’s 36 — she was born in 1979 and we left school in 1997.”
Overnight, Wilson poked fun at the press and decided to reveal the truth about her real identity.
Well, sort of.

Earlier, the unnamed source provided the magazine with a photo of “Melanie Bownds” in a debating team school photo. A plaque positioned in front of them states: “1997 Year 12 Commonwealth Bank Debtaing (sic) Team”.
“She was definitely not the class clown; none of us remember her being funny,” the source tells the mag.
And despite Rebel’s depiction of a crazy, “bogan” upbringing, the source says she actually had a “very normal, upper-middle-class upbringing”.

Just IMO though.