Gwen Stefani and Blake Shelton are reportedly trying for a baby.

Gwen Stefani and Blake Shelton

Gwen Stefani and Blake Shelton

The couple - who have been dating for two years - are keen to tie the knot in the near future but are said to be "hyper-focused" on getting pregnant beforehand as the 48-year-old singer is concerned her age may affect her chances of conceiving.

A source told Us Weekly magazine: "They will get married one day but right now they are hyper-focused on getting pregnant. They believe there is still a chance for Gwen [to fall pregnant]. They are incredibly hopeful.

"Gwen and Blake started talking quickly about having a baby, but starting a family has not been easy for them. It's something that they really want and it's just not working out the way they wanted it to."

The 'Hollaback Girl' hitmaker already has sons Kingston, 11, Zuma, nine, and Apollo, three, with her ex-husband Gavin Rossdale, but she's keen to have another little one because she knows how much Blake wanted a family with his ex Miranda Lambert.

The insider explained: "Blake told Gwen he does want kids of his own and Gwen was willing to try. With her, Blake has the exact relationship and family life he'd hoped to have with Miranda. Gwen's everything he wants. They are so committed to one another."

Meanwhile, the 41-year-old musician is keen to prove how serious he is about the blonde beauty by converting one of his old inkings into a tribute piece for her.

A source said recently: "Blake's never liked the tattoo he has on his forearm, he always says it's ugly. He's talked about covering it up for a while and the only reason he hasn't is he can never decided on a design.

"But he's working on it, sketching ideas has turned into a little hobby for him. Now he's trying to figure out a way to work a tribute to Gwen into the new design."