Kristin Cavallari and Mark Estes have called it quits on their romance.

The news was report by multiple outlets Sept. 27, soon after the Hills alum appeared to confirm the split while chatting with Call Her Daddy podcast host Alex Cooper onstage at her Unwell Tour show in Austin, Texas.

"It's so fresh," Kristin said. "My plan was not to say it."

E! News has reached out to Kristin and Mark's reps for comment and has not heard back.

The news comes just one day after Kristin's former Hills costar Jason Wahler expressed his support for Kristin while singing Mark's praises. "Dude, if Kristin's happy, like all for it," he exclusively told E! News cohost Keltie Knight at the 2024 People's Choice Country Awards Sept. 26. "He's a really cool guy. He's a really sweet guy."

Kristin, 37, went public with her romance with Mark, 24, in February, sharing a cozy-looking selfie on Instagram with the caption, "He makes me happy."

The Uncommon James founder later revealed on her podcast that the two began dating after the TikToker had slid into her DMs using his group's account, writing, "I love you."

During the course of their relationship, Kristin and Mark encountered some criticism from the public over their 13-year age gap. Both brushed it off.

"She makes happy, I make her happy," Mark told E! News in March 21. "That's what's important, so I'm not too worried about the critics, honestly."

Over the last few months, the Laguna Beach alum introduced her boyfriend not only to her former costars but also to her kids, Camden, 12, Jaxon, 10, and Saylor, 8, who she shares with ex-husband Jay Cutler.

"My kids love him," she told E! News’ Francesca Amiker in August. “He loves my kids. He actually took my kids to school, and it's just—he fits in very well. And I'm really thankful for that.”

And early on in her relationship with Mark, Kristin did not rule out the possibility of trying to conceive a child with him.

"The one thing that I'm not actively thinking about it, but it's definitely in the back of my mind, is he wants to have a kid," Kristin said on the April 2 episode of her podcast Let's Be honest. "I'm mulling it over."

She added, "If he ends up really being the one, I would have a kid."

The Very Cavallari alum later played down the matter. "It's too soon to tell," Kristin said on the April 16 episode of her Let's Be Honest podcast. "I've been dating Montana for a couple of months. We're just gonna slow our roll and continue to date."

She added that while she was "not in the works to have a new baby daddy," she did have the "kid conversation" with Mark, clarifying, "I have the kid conversation with everybody I go out with."

The pair revisited the subject again on her podcast earlier this month.

"I think my end goal, obviously," Mark began on the Sept. 3 episode of Let's Be Honest, "would be to be married and have a happy life.”

Kristin teased, “Have a baby, you can say it.”

“I mean,” Estes began, “that’s in there.” 

The two also shared some NSFW thoughts on their romance.

"You’re the best sex I’ve ever had," Mark told Kristin, who concurred, after which he confessed, "I’m obviously so in love with you so that helps."

Look back at Kristin and Mark's romance...

Kristin Cavallari debuted her romance with Mark Estes in February 2024, captioning this photo of the couple, "He makes me happy."

"Photo dump of my girl and I," Mark wrote on Instagram March 2024.

Among the snaps included a picture of the pair sharing a rooftop kiss.

The Hills alum got cozy with her man in the series of photos.

Mark wrapped his arms around the Kristin during a night out on the town.

Kristin captioned this cozy-looking shot in March 2024: "Him."

The couple hit up the Stagecoach Festival in California April 2024, with Kristin captioning a photo of herself kissing Mark on Instagram, "Cowboy take me away."

The Very Cavallari star visited Mark's native Montana in May 2024.

Kristin and Mark enjoyed a staycation at Tennessee's Bolt Farm Treehouse in early June 2024.

In late June 2024, the couple took a vacation to the Bahamas—where they were joined by Kristin's Camden, Jaxon and Saylor, who she shares with ex-husband Jay Cutler.

Kristin captioned photos of the tropical getaway, "Bahamas with my favorite people."

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