Erin Foster doesn't want to be anything other than honest.

The O.C. alum got candid on her past dating life, alleging that ex Chad Michael Murray cheated on her with One Tree Hill co-star Sophia Bush during their romance, which lasted from 2001 to 2002.

"You actually dated a lot of celebs," Sara Foster told sister Erin on a recent episode of The World's First Podcast while reading a news article about their former flames, per Entertainment Tonight.

"In it, it said, 'And he apparently cheated on her with Sophia Bush,'" Sara said. "By the way though, DeuxMoi's not—they don't lie. I mean, and that is what happened."

To which Erin, 41, agreed. "I mean, yeah," she said. "He definitely did cheat on me with her in, like, a pretty egregious way."

The Barley Famous star alleged the affair happened while she was living with Chad, adding sarcastically, "Pretty cool."

Chad, 42, went on to tie the knot with Sophia in 2005, though they separated just five months later. 

Sophia has since expressed that she felt pressured to get married to the Cinderella Story alum, telling Andy Cohen on his Radio Andy Sirius XM show in 2018 that "it was not a thing I actually really wanted to do."

She recalled that she was just starting her career at the time and was trying to focus on acting.

"I wasn't looking for a relationship, but one found me and became serious, even though I hadn't planned to settle down until my 30s," Sophia wrote in Cosmopolitan in 2017. "But when the person you're with asks you to marry him, you think: 'This must be happening because it's supposed to.'"

The 41-year-old said she will "refuse to let that one relationship define me," which is why she tried to "avoid discussing it" for a decade. 

"The reality is that, yes, it was a massive event in my life," she continued. "And the trauma of it was amplified by how public it became, which was incredibly foreign and bizarre to a girl who'd been just another college kid 24 months before her life blew up."

Sophia—who has said she's no longer "allowed" to talk about Chad publicly—went on to marry entrepreneur Grant Hughes in 2022. However, by August 2023, their relationship was over the hill and done with as she filed for divorce.

She's since started dating soccer star Ashlyn Harris, according to multiple reports, who is in the midst of her own divorce from fellow sports champ Ali Krieger. 

Ali cryptically hinted at infidelity in an Instagram post on Oct. 19, writing that she is "preparing for playoffs while in my Beyonce lemonade era." 

E! News has reached out to reps for Chad, Sophia, Ashlyn and Ali but hasn't received a comment.

Fall in love with these photos of recent One Tree Hill reunions:

Michael Trucco and James Lafferty photoshopped a sign to pay tribute to the show. "Sign seems legit," Michael wrote. "Always a good day when I get to spend time catching up with my buddy/nephew."

James Lafferty and Bryan Greenberg had a mini One Tree Hill reunion and were joined by Jamie Chung and Alexandra Park.

As Hilarie shared, these three will always be there for another, through "thick and thin."

Fans were loving this reunion, including Kristin Cavallari, who commented a heart on the post.

Hilarie and Robert give the camera a cheeky look in this selfie.

It's safe to say these former cast mates will be BFFs.

Clearly, someone cannot contain their excitement over this reunion. 

Throughout the many seasons of One Tree Hill, fans got to know and love many a character, including Michael Trucco's Cooper. As die-hard fans will recall, the conniving Rachel seduced Cooper and tricked him into thinking she was having his baby in the second season. The gig was up, however, when they both got in a car accident and she had to confess she lied about the whole thing, thus leading to Cooper's exit. 

Hilarie poses with the famous Angel of Death character that used to plague her.