Billboard music awards 2016
Gwen Stefani and Blake Shelton on stageGetty

Gwen Stefani has showered her boyfriend Blake Shelton with adorable throwback photos on Twitter and Instagram. The Rich Girl singer not only wished him on his birthday on the micro-blogging site, but also changed her Twitter avatar to a picture of the 40-year-old.

"Happy birthday to my favorite person I ever met @blakeshelton," the 46-year-old singer captioned an old picture which shows a much younger Shelton on Twitter. She further followed up the post with cute cow, bee, and sunflower emojis before adding "#superbabe", she wrote.

The love from Stefani's end was soon echoed by Shelton who retweeted his girlfriend's adorable post with the caption, "Now THIS is how you start your 40's!!!!!!!! Thank you @gwenstefanifor everything..." Clearly the music power couple were in no mood to round up their birthday wishes and exchange of love with just one Twitter post, as The Sweet Escape hitmaker next took to her Instagram account to share another photo of Shelton as a young boy.

"Happy birthday to @blakeshelton literally my favorite person gx," she shared along with a grainy old picture of a young Shelton smiling into the camera.

The Voice coach's relationship with Stefani began seven months back, when both the singers were struggling through a rough patch in their respective marriages. Within weeks of Shelton divorcing his then wife Miranda Lambert in July last year, Stefani too announced the news of her split from husband Gavin Rossdale. And, as the singers' romance unfurled over time, the duo became famous for their chemistry, with Stefani even finishing Shelton's song, "Go Ahead And Break My Heart."

"I sent it [the song] to her just half done...and she wrote the next verse and sent it back to me. And so it was like, oh, we've got a song together," Shelton had said earlier.

The country singer has been quite vocal about his love for Stefani time and again. "Gwen saved my life last year. It's not something anybody could've seen coming besides God I guess because it doesn't look like it would make sense... It just makes the most perfect sense for us and where we're at in our lives," he had said during an interview.