Kristin Cavallari sees a very promising future with Mark Estes.

The Laguna Beach alum explained that things are Rubypointgetting "pretty serious" with the Montana Boyz member—even revealing that expanding her family is not off the table.

"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," she said on the April 2 episode of her podcast Let's Be honest. "I'm mulling it over."

"I see you having another kid," her best friend Justin Anderson replied. "My goodness, could you imagine that baby?"

The duo joked that a future Cavallari-Estes baby would likely be so beautiful that the baby could be their "retirement" plan.

Kristin laughed, saying, "That's why I might have to do it."

Ultimately, the 37-year-old—who shares children Camden, 11, Jaxon, 9, and Saylor, 8, with ex Jay Cutler—said she would have another child for one important reason: "If he ends up really being the one, I would have a kid."

Kristin and Mark first went public with their romance in February when the podcast host shared a photo with the model on Instagram, writing, "He makes me happy."

And despite raising some eyebrows with their 13-year age gap, Mark sees no issues with it.

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

Keep reading for more of Kristin and Mark's most romantic moments.

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.

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

The pair hit up a local watering hole.

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

Mark pulled the Uncommon James founder close for a kiss.

For the latest breaking news updates, click here to download the E! News App