Blake Shelton turned to social media on Saturday (Oct. 3) to post a sweet birthday message for his longtime girlfriend, Gwen Stefani, sharing that there's one special thing he wishes he could do for her "every single day."

Stefani turns 51 on Saturday, and her boyfriend and fellow coach on The Voice posted a picture of them singing together to Instagram alongside his birthday message.

"It’s a special day for a special lady in my life. Happy birthday @gwenstefani," Shelton writes, adding, "I’d write a song for you every single day if I could..."

The couple have made plenty of beautiful music together since they began dating five years ago after meeting on the set of The Voice. They teamed for "Go Ahead and Break My Heart" in 2016, and sang together again in 2017 on a Christmas duet titled "You Make It Feel Like Christmas." Their recent collaboration, "Nobody But You," landed them a multi-week No. 1 hit at country radio, and they followed that up by releasing another duet titled "Happy Anywhere."

Shelton and Stefani spent the bulk of their coronavirus quarantine together with Stefani's three children at Shelton's ranch in Oklahoma during the pandemic, and they have purchased their first home together, a spectacular 13,000-square-foot, $13.2 million mansion in California's San Fernando Valley. According to reports, the couple moved into their new home in time for the new school year to begin.

See Blake Shelton + Gwen Stefani's Stunning California Mansion

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