Blake Shelton and Gwen Stefani write new song together

He's a little bit country, she's a little bit rock n' roll.

No doubt Blake Shelton and Gwen Stefani have a lot to write about after both going through divorces this year and, just this week, announcing their romantic relationship.

A source confirms to ET that the musicians have penned a song together, but it's yet to be confirmed if the new couple have recorded it yet.

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Shelton, 39, split from Miranda Lambert, 31, after four years of marriage in July, while Stefani, 46, filed for divorced from Gavin Rossdale in August after nearly 13 years of marriage. Coincidentally, they're both mentors on this season of The Voice.

Stefani has already come out with a breakup song since her split, titled "Used to Love You."

See photos of Blake and Gwen together since joining 'The Voice':

With lyrics that include "I guess nobody taught you how to love," and, "You go, I'll stay, you can keep all the memories," it's not difficult to see how it might be about Rossdale, 50.

WATCH: Miranda Lambert 'Was Hurting' After Blake Shelton Confirmed Gwen Stefani Relationship

"The biggest gift has been to be able to take some tragedy and write a song about it and share that," the mother-of-three told ET in October. "The rewards that I've gotten through that is just unbelievable."

While we've yet to hear Stefani and Shelton's song, we have seen them on stage together. While on The Tonight Show starring Jimmy Fallon, the duo were asked to perform Drake's "Hotline Bling," but things got awkward when Shelton admitted he wasn't familiar with the track.

MORE: Adam Levine Calls New Couple Blake Shelton and Gwen Stefani 'Family' in Candid Photo

Now that the two have gone public about their romance, perhaps we'll see more PDA between them. ET already spotted Stefani and Shelton holding hands while out and about in Nashville, Tennessee on Wednesday.

Check out the exclusive pics: