Mat Johnson welcomes first child, announces birth on Instagram

Mat Johnson, a star on The Block's 2025 season, announced the birth of his first child, a baby boy conceived via IVF with his friend Leah Cocks. The 41-year-old reality TV personality revealed the news in an Instagram post on Friday, sharing photos of the newborn and the moment of arrival. The couple plan to co-parent the child, and Johnson has not disclosed the baby's name.

'Yesterday my life changed forever,' Johnson wrote in the post. The announcement drew congratulations from followers, including Real Housewives of Melbourne star Jackie Gillies, and from Johnson's Block circle, such as co-host Shelly Craft and fellow Block stars Alisa and Lysandra Fraser. Craft responded with a hearty 'Congratulations family,' to which Johnson replied, 'Thanks, Auntie Shelly.' The post featured multiple photos, including a shot of Johnson cradling the infant beside messages of support from fans and friends.

Johnson and Leah Cocks have known each other for roughly two decades, dating back to when she first sat in his hairdressing chair. The couple, who are raising a baby together, planned to co-parent after deciding to start an IVF journey. Leah, who is in a same-sex relationship, learned she was pregnant just a week after Johnson and Block co-star Robby Lippett began their Block build, though she waited to share the news until Johnson had returned. A year later, Johnson said he had a change of heart and the couple began their IVF journey, which took several years to come to fruition. The birth marks a new chapter for the group and adds a new dynamic to the show’s ongoing narrative about family and choice.

In October, Johnson spoke to New Idea about his long-held dream of fatherhood. He said he always wanted to be a dad, even later in life, but admitted he was initially reluctant when Leah proposed co-parenting. 'I didn’t know if I was ready at that stage of my life, and I think I was terrified because I have a very good life that I worked decades to be able to have,' he said at the time. The couple’s decision to pursue IVF followed, and the journey extended over several years before the birth materialized.

The news comes amid goodwill from Johnson's Block colleagues. Block co-host Shelly Craft joined in with supportive comments on the birth, while fellow season seven stars Alisa and Lysandra Fraser offered congratulations and encouragement about the new fatherhood chapter. Johnson has also spoken about balancing personal milestones with professional commitments on the reality program, including a recent auction day that did not meet his expectations. Earlier this year, Johnson and Robby Lippett walked away with $109,999 from an auction, which he described to 9Entertainment as not great but accepted as part of the business. 'It's not about the money... but it's about the money. Just to cover my costs for not being in the business or the work I said no to, it wouldn't even cover that,' he said at the time.

The latest development adds a personal triumph to Johnson’s public arc, intertwining his reality TV fame with a growing family narrative that will likely follow him through the remainder of The Block’s current season. Followers and fans are expected to follow the family’s journey closely as they navigate co-parenting, IVF timelines, and the realities of life in the public eye.