He had initially hoped to do it with his now-ex-wife Katy Perry - whom he divorced in 2012 following two years of marriage - as well as his former flame Jemima Khan, whom he split from in 2014, but things didn't go according to plan.
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The insider explained: "Russell is absolutely made up [about the prospect of becoming to be a dad]. Most of his closest friends have children and he was desperate to start a family.
"It didn't work out with Katy, who felt she was too young for kids - and there were conversations with Jemima."
Laura - the younger sister of TV presenter Kirsty Gallacher - first began romancing Russell in 2006 but their relationship was short-lived and it came crashing down in 2007.
They then set tongues wagging about a possible reunion when they were spotted looking cosy again in public in 2009.
However, their chemistry seemingly fizzled out and they've lived separate lives - dating new people - until they rekindled their relationship last year in Rome.
- Bang! Showbiz