The former TOWIE star and his ex-Coronation Street actress wife Michelle are often hailed as one of the most good-looking couples in showbiz, which Mark says is putting pressure on them.
Appearing on ITV's Loose Women today, he joked: "It's hard work with the pressure of having babies! Everyone is like, 'Your kids will be so beautiful.' We'll probably give birth to an ugly duckling and let everyone down."
He did clarify he was joking and all they wanted was a healthy baby when the time came.
Mark said it was TOWIE star and cousin Elliott Wright who inadvertently caused his mum Carol to get on the baby bandwagon. "My auntie Debbie is in the audience today. She's the first of the aunties to become a grandmother with Elliott's kids. She told my mum every day that being a grandmother is much better than being a mum so now my mum is on our case. Hurry up and make it happen! I want to be a nan!"
He jokingly added: "I think I have got about another year or two and then I'll have to do it."
Mark also said that Michelle's going off to Africa to film Our Girl for BBC next month, saying: "If the papers are anything to go by, she went away at Halloween but she doesn't go until next month so I have a couple more weeks.
"We'll talk on FaceTime. It saves a lot of agg! Same as we do when I'm filming Take Me Out: The Gossip. She doesn't come and I'm away for a month so we FaceTime and phone each other."
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