The duo enjoyed a cozy night together at Clive Davis' Pre-Grammy Gala in February, and on Tuesday, the "Complicated" singer posted a photo of herself with her ex at the recording studio.
With guitars in hand, the two musicians have bright smiles on their faces as they pose together on a couch in the photo Lavigne posted on her Instagram.
In another snap, the singer shows off their collection of instruments and a Hello Kitty notebook (perhaps they're penning some tunes about their relationship?).
"It is with [a] heavy heart that Chad and I announce our separation today. Through not only the marriage, but the music as well, we've created many unforgettable moments," Lavigne wrote in September on her Instagram. "We are still, and forever will be, the best of friends, and will always care deeply for each other."