Mischa Barton & Rachel Bilson: Clash Of The Costars!

The OC Mischa Barton and Rachel Bilson

The OC alums Mischa Barton and Rachel Bilson “never got on well,” says an insider, and now it seems their mutual dislike has gone up a notch. “There’s resentment that goes back to the show, when Mischa was the more popular one,” says the insider, noting that her It Girl status “didn’t sit well” with Rachel.

In May, Mischa Barton, 35, seemed to diss her former castmate when she said things got more difficult in season 2 of the hit series, after Rachel Bilson ‘s “last-minute” promotion. “She was pretty steamed,” the source says of Rachel, 39, who hit back on her Welcome to the OC; B**ches! podcast.

Youtube – Access. Rachel dismissed Mischa’s claims that her title bump was a surprise and said she was “confused” by her claims of being bullied on set.

While Mischa said there were people on set that were very “mean” to her, Rachel claimed she didn’t know “who or what she was referring to.”

“The gloves are off,” adds the insider, “and you can expect the badmouthing to continue.”