In a sneak peek at Sunday’s episode of Total Bellas, the pro wrestlers sit down for a candid heart-to-heart — and Bella, 34, makes her position on having kids loud and clear.

“I don’t think date nights could ever get old,” she begins. “But I think so many years down the road, to keep things exciting, kids help that in a relationship. I just see the point of kids after you’ve been with someone for so long.”

But Cena, 41, isn’t on the same page.

“In a hypothetical universe say I was like, ‘Okay, we’re going to have kids.’ And we do — and you find out that wasn’t the real problem,” he says. “And then years from now you look at me and resent. So I’m talking to you tonight and I’m trying to ask all these difficult questions, because I don’t know if you’re just upset that you’re not going to be a mom, or you have fallen out of love with me. Because it kind of feels like both. There’s no way that I can interpret your actions over the past three months as anything different.”

Bella, however, insists that their issues lie in their differing stances on having kids.

“I just want to be a mom, to constantly wake up and look at this beautiful thing that I made,” she says. “I feel like there’s so much more I want to do with you and experience with you.”

“It’s just wanting to be a mom and knowing you will not be a dad,” she adds. “So it’s me who has stuck around thinking I could be okay with it, and I’ve just come to the realization that I can’t — I’m not okay with it.”

And with that, Cena reveals he’s finally willing to come around.

“So it literally is just about being a mom?” he says. “Okay. Because I can’t have you out of my life, ever. I want to marry you. And relationships and marriage, especially, is about sacrifice. And I will make that sacrifice for you. I will give you a child.”

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The couple called off their wedding in April after six years together but were spotted out together in May. PEOPLE confirmed earlier this month that they are officially back together.

The pro wrestlers had been open about their desire to reconcile, with Bella previously telling PEOPLE that she’d been in “communication” with her ex.

Earlier this month, Cena publicly confirmed that after years of insisting he had no desire to start a family, he’d had a change of heart.

“I would love to be a dad,” he told TMZ. “I dedicated my life to my work, and now I’m realizing that there is life, and life exists, and it’s beautiful, and I think part of that is being a parent.”

Total Bellas airs Sundays (9 p.m. ET) on E!