England and Arsenal footballer Theo shared the couple's happy baby news on Saturday, 26th November, simply saying: "Welcome to the world little brother, Arlo."
He added a gorgeous photograph to Instagram showing their elder son Finley, two, holding his baby brother's tiny hand.
Physiotherapist Melanie, 26, revealed her pregnancy to Theo on his 27th birthday back in March, later telling Hello magazine: "I knew it was the best present he could have wished for. Theo's a real family man and an amazing dad."
At the time, the couple didn't know their child's sex, with Melanie saying: "I see myself with a girl but at the same time I can picture Finley with a little brother because he's such a boy."
Theo celebrated little Arlo's arrival in style over the weekend, scoring for Arsenal in their game against Bournemouth. He dedicated the goal to his newborn son.
Childhood sweethearts Theo and Melanie became engaged on New Year's Eve in 2011, after Theo popped the question at their Hertfordshire home. They started dating after meeting at a local shopping centre when they were just 15.
They married at an Italian castle in June 2013.
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