Blake Shelton’s “Coolest and Craziest” Birthday

Gwen Stefani Pops Into Colorado for Duet

It was cool. It was crazy. And it was probably the best birthday Blake Shelton will ever have.

When Blake Shelton was playing at the Country Jam festival in Grand Junction, Colorado, on Saturday night (June 18) night, Gwen Stefani had joined him on stage to celebrate his 40th birthday.

“So I possibly witnessed the coolest and craziest thing of my life tonight. … Thank you Colorado and @gwenstefani!!! Look up the videos,” he said to his social media followers, adding later, “Now THIS is how you start your 40’s!!!!!!!! Thank you @gwenstefani for everything…”

According to Billboard, they sang “Go Ahead and Break My Heart,” than Shelton admitted to the crowd, “I guess if I had one birthday wish for me personally, I wish I could rock.”

Stefani also did No Doubt’s 2002 hit song “Hella Good,” which Stefani co-wrote with Pharrell Williams way back before the group got to know each other on The Voice.

She also used Shelton’s birthday as an excuse to post an adorable picture of him on Twitter as a little boy.