Singer and author Geri Horner is mum to two children, Bluebell, aged 17, and six-your-old Monty, whom she shares with her husband, Red Bull Formula One boss Christian Horner. Geri is also step-mum to Christian’s daughter Olivia. There is a ten-year age gap between Geri’s two children, yet she welcomed both at the same hospital, London’s exclusive Portland, and she …