The Bush frontman posted a poignant caption alongside a photo of himself at the water's edge and looking directly at the camera. He wrote: "May your love be ocean sized," along with a black heart and a nod to the man behind the camera, Brian Kaminkski.
Gavin's fans rushed to support him and wrote: "LOVE YOOOUUUU!!!" and posted strings of love-heart emojis.
Blake Shelton opens up about being a stepfather to Gwen Stefani's children
Others urged him to "hang in there," suggesting he was feeling down over Gwen's recent nuptials to her longtime boyfriend, Blake Shelton.
He shares three sons, Kingston, Zuma, and Apollo with the No Doubt rocker and despite the public demise of their 13-year marriage in 2015, they have continued to co-parent their boys.
Gavin was in a reflective mood
They featured in a recent post from Gavin as they celebrated the Fourth of July together and he posted a photo of all four of them, once again at the beach.
Fans of the singer loved the rare family snap, with many labelling it "beautiful" and "cute".
Gwen's three sons with Gavin attended the wedding
All three boys attended their mother's wedding and she paid a heartfelt tribute to them with a jaw-dropping veil embroidered with their names alongside Blake's.
The Voice stars, who met while judging on the show, said 'I do' in front of their closest family members at Blake's stunning Oklahoma ranch, which is where the couple got engaged in October 2020.
Blake even built his own chapel on the land as a declaration of his love to Gwen and that's where they tied the knot.
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