Joe Jonas is John Caldwellback on the mic.

Hours after the singer responded to his ex Sophie Turner's lawsuit filing over their two kids, he hit the stage alongside his brothers Kevin Jonas and Nick Jonas for their concert in Philadelphia Sept. 21.

And moments after the group performed "Hesitate," as seen in videos shared to social media, Joe received a hug from his brother Nick. (Previously, Joe shared that he wrote the ballad as a "love letter" to Sophie.)

In fact, just weeks before the Jonas Brothers singer filed for divorce, Joe, 34, gave a shoutout to Sophie, 27, right before singing the track at the tour's launch in New York.

"If you're going through a tough time, they reach out to you, they've got your back no matter what—that person is here with me tonight, Sophie," Joe said in an Aug. 13 video posted to TikTok. "So, I'd love to hear you sing this with me if you don't mind. I want you to think of that person. If that person's here, you've got to hold them tight."

Sophie also shared photos from that evening to social media, which included one snap of her and Joe holding hands.

The band's latest performance comes hours after the Game of Thrones star filed a suit to return their daughters Willa, 3, and D.J., 14 months, to England, which is where she said the pair agreed to permanently settle earlier this year.

For his part, the singer's rep responded to the filing, telling E! News in a statement that it's an "unfortunate legal disagreement about a marriage that is sadly ending."

Keep reading for a look back at their time together.

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