Selena Gomez and Demi Lovato reunite at 2017 InStyle Awards

Selena Gomez and Demi Lovato's relationship is "Simply Complicated" -- but they're officially turning over a new leaf.

The former Disney Channel stars are childhood friends who essentially rose to fame together, but over the years, their relationship has suffered fractures. Although many still associate the two with each other, they began going their separate ways more than six years ago.

Selena told Seventeen, "I've known her since we were seven, and we did fall apart for awhile. She was going through things and I was so young and it was confusing. I processed it saying, 'OK, I don't understand what she's going through, so I'm just going to do this.' I don't think it was fair, and I'm so happy that I have her back in my life now."

But just months later, they had unfollowed each other on social media.

It wasn't until this year that the two began interacting again online. Demi congratulated Selena on her song "Fetish," and in October, Selena had nothing but positive things to say about Demi's revealing documentary.

"This was beautiful. I'm so happy for you," she wrote on Instagram. "You always continue to [be] bold and real. I wish more people were like you. Love you."

Since they hadn't posed together on the red carpet since 2011, few expected what happened Monday night: Demi and Selena reunited for a sweet, smiley photo at the 2017 InStyle Awards.