Spencer Pratt Claims Kaitlynn Carter and Miley Cyrus 'Had Something Going On' While Filming 'The Hills'

"The Hills: New Beginning's" star Kaitlynn Carter already "had a thing going" with Miley Cyrus before she split from Brody Jenner -- at least, according to Spencer Pratt.

Following Monday's episode of the MTV reality show -- where Kaitlynn and Brody addressed rumors the now-separated couple had an open relationship -- Spencer claimed, via Cosmopolitan's "Hills" recap, that Kaitlynn and Miley had something going on behind-the-scenes before Kaitlynn and Brody broke up.

"It's tough for me to listen to Kaitlynn complain about people talking about her allegedly open relationship with Brody when we know she had a thing going with Miley," Spencer told the publication. "She already had something going on with her when these scenes were filming -- maybe not physically, but definitely emotionally."

"No one's judging you for whatever it is you and Brody do when he's not sleeping in his car," he continued. "We just don't want people to lie about their lives."

"Maybe you shouldn't have gone on television," he added. "It's called a reality show, hon. And the reality is that Brody's been talking about your sex life on his podcast for years."

Spencer then poked fun at when Kaitlynn recalled the beginnings of her relationship with Brody during one point in the episode.

"My favorite is when she's like, 'Brody and I were wild, young, crazy kids,'" he said. "Was that last week? Because you and Brody have only been together a minute. Are you older and more mature now that you're chilling on Miley's yacht?"

If you recall, a few weeks after Kaitlynn and Brody announced their split last month, Kaitlynn was photographed kissing Miley while on a girls trip to Italy. One day later, Miley and Liam Hemsworth announced they were separating after less than a year of marriage.

Also during Monday's episode, Kaitlynn said her co-stars lacked "common decency" when it came to discussing her and Brody's marriage. Unsurprisingly, Spencer had some thoughts on that too.

"I would love to know Liam Hemsworth's thoughts on Kaitlynn's recent displays of 'common decency,'" he added to Cosmo. "You know what I call 'common decency'? Getting it on at your Italian villa and not in front of the paparazzi."

We have a feeling there is much more Kaitlynn-Miley commentary to come from Spencer.

"The Hills" airs Mondays on MTV.

Got a story or a tip for us? Email TooFab editors at tips@toofab.com.