Stefani, 47, was smiling for the holiday photo that she posted on Saturday via Instagram. The singer captioned it, "Had the best Thanksgiving."
Shelton, 41, is embracing his girlfriend and The Voice co-star and bussing her on the cheek in the photo. In the side view of Stefani's belly, her sweater makes her look pregnant.
"Does Gwen have a baby bump? Congrats," one fan commented on Instagram.
Another asked, "it's a baby bump?"
But this isn't news to RadarOnline.com readers, as Stefani has showed her burgeoning belly before, most recently in a skintight mermaid costume.
The former No Doubt singer has also used a big purse to shield her bulging tummy.
Sources have told Radar that Stefani has undergone IVF treatments to get pregnant with Shelton.
The Voice judge, who met co-star Shelton, while appearing on the NBC reality show, is already a mom to sons Kingston, 11, Zuma, 9, and Apollo, 3, with ex-husband Gavin Rossdale.
But Shelton, who was previously married to fellow country singing star Miranda Lambert, hasn't had kids yet.
According to a Radar insider, Stefani and Shelton have been secretly planning for her to get pregnant for months.
Shelton has often been seen having fun with Stefani's kids and enjoying holidays with her family members. He celebrated Easter with his lady and all of her relatives. On Thanksgiving, he again bonded with Stefani's kin.
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