WWE stars John Cena and Nikki Bella split earlier this year, just weeks before they were due to get married, with their differing attitudes to having children partly being blamed for their rift.
However, the 'Blockers' actor has since had a change of heart and is now open to having a family, but it seems there have also been medical reasons behind his unwillingness to have kids.
In scenes aired on Nikki's reality show 'Total Bellas', the former couple reunited for a romantic dinner and John said: "I wanna marry you and relationship and marriage especially is about sacrifice, and I will make that sacrifice for you. I will give you a child."
Nikki replied: "But you have the..."
John said: "I know. I physically can't have kids. So, I'm also telling you that I'm willing to have surgery and then still go through with being a dad."
Nikki was initially stunned by the 41-year-old sportsman's promise.
She said: "You're sure though? Are you gonna change your mind?"
When John promised he wouldn't go back on his word, she exclaimed: "Oh John, you're gonna be the most amazing dad in the world."
The 34-year-old star was so thrilled by John's pledge, she jumped across the table into his arms.
She later admitted to the camera: "I think I'm gonna leave here as a fiancée. I think, yeah. I am still the soon-to-be Mrs. Cena."