The former Spice Girl star welcomed Montague George Hector Horner into the world on Saturday morning.
‘Monty’, as he’s already been nicknamed, is Geri’s first child with Formula 1 racing team boss husband Christian Horner.
A family source told The Mirror: “Geri wanted George to be a part of Monty’s life, so she felt it only fitting that her newborn have a middle name after the star.”
Geri already has a 10-year-old daughter, Bluebell Madonna, from a previous relationship. She also has a connection to the late ‘Careless Whisper’ singer, as she is the goddaughter of his ex partner, Kenny Goss.
Shortly after the birth, the 44-year-old former Ginger Spice shared an Instagram snap of her son’s foot with the caption: “Montague George Hector Horner arrived this morning, a beautiful little brother for Bluebell and Olivia #amazing-day #grateful #monty.
And she added on Twitter: “Christian and I are delighted to announce our baby boy was born this morning weighing 7lbs 8oz.”
Fellow Spice Girl Emma Bunton, who now shares a birthday with Monty, was one of the first to congratulate Geri on her new arrival.
Geri posted a picture of the pair in their Spice Girl days as a special birthday tribute and the former Baby Spice responded: “Amazing news, so happy! Birthdaytwins, birthdaymade. Love you all.”
Meanwhile, Christian’s uncle Geoffrey Kenyon May said he was “delighted” at the news of the new arrival to the family.
“They are both happy and the baby is fine,” he told The Mirror.
Asked if they would have more children, he added: “I think it is pushing the boat out but anything is possible.
Wham! star George was found dead on Christmas morning, aged 53, by boyfriend Fadi Fawaz.
Following the tragic news, Geri posted: “So so sad, RIP George, a dear friend, the kindest, most generous and talented person.”