Gwen Stefani and Blake Shelton on The Voice Credit: Trae Patton/NBC

Blake Shelton popped the question to Gwen Stefani. The country singer, 39, proposed that his girlfriend of two months, 46, serve as mentor to his team on the upcoming season 10 of NBC’s The Voice, a source reveals in the new issue of Us Weekly. (Christina Aguilera is returning to fill Stefani’s coach chair when the hit singing competition returns February 29 at 8 p.m.)

The hunky country crooner hinted as season 9 was drawing to a close in December that he’d like to keep his lady on the set. “I don’t want Gwen to not be on the show. Why can’t we have a fifth coach?” he told Extra at the time.

But when the lovebirds aren’t working together, they’re jet-setting around the country. Just two days before filming in Los Angeles January 11, Stefani was Shelton’s date to the nuptials of his hairstylist, Amanda Craig, at the Loveless Barn outside Nashville.

“Gwen and Blake were kissing and slow dancing most of the night,” a source says of the pair at the reception, which featured a Motown band that played for guests including Kelly Clarkson and The Voice alum RaeLynn. “Blake was looking at Gwen like she was the only woman in the world!”

But could wedding bells soon be ringing for the couple outside of Tennessee? At the end of the reception, Stefani caught the bouquet! “She was smiley and super cute about it,” the source adds. “Blake came up and gave her a kiss.”

After the festivities, the two skipped a hotel room, opting to bunk in Shelton’s multimillion-dollar luxury tour bus instead. “They parked right outside the venue!” an eyewitness observed.

And apparently, Stefani’s happiness is so obvious, an insider says ex-husband Gavin Rossdale has taken note. “Seeing Gwen so crazy in love is killing him,” the source tells Us. “He had hope that they would get back together, but knows there’s no chance of that now.”

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