The TV star looked right at home as he snuggled little baby Brody, who Michelle's cousin Katie Fearnehough welcomed last week.
WATCH: Michelle Keegan and Mark Wright's love story
Sitting on a sofa with Brody sweetly sleeping on his chest, Mark confessed his love for the little tot, writing: "The day I met Brody. New member to the clan. Gorgeous little boy. @katiefearnehoughx & Tony he is beautiful!! Love him already."
Mark Wright cosied up to new baby Brody
Fans were quick to coo over the newborn and quiz Mark on when he and Michelle might welcome a baby of their own. "Your turn next Mark," said one. "You so need your own!" exclaimed another. A third added: "Superb photo. When are you getting one of your own?"
Both Mark and Michelle have constantly fielded questions about when they will start a family, with Michelle previously admitting she feels frustrated by the constant speculation.
Brody is the son of Michelle Keegan's cousin
In an interview with Cosmopolitan, she said: "A few years ago it didn't bother me and I answered the question, but now I think, 'I don't need to answer that because nobody knows what goes on behind closed doors.'
"I remember when I finished Our Girl, people were like, 'Is it because you’re going off to have a baby?'"
How cute is he!
She continued: "I know for a fact if Mark finished a job, nobody would ask him if he was going to have a baby. It's not fair. It does make me feel frustrated."
If the couple decide to have a baby in the future, however, they have already agreed on one very important decision – the name!
Mark and Michelle married in 2015
Speaking on his Heart Evening Show to Robbie Williams, Mark jokily asked permission for the couple to name their daughter after Robbie's eldest child, Teddy.
He said: "I mean she saw a picture I think of you and the family - and said, 'Oh I love that name so much'. I’m asking you if it comes to it and she wants to call the kid Theodora or Teddy, are you gonna be alright with that?"
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