Selena Gomez -- who once dated Joe's younger brother, Nick -- also had a message for the newly engaged singer.
Demi Lovato didn't let her romantic history with Joe Jonas get in the way of celebrating his recent engagement to Sophie Turner.
On Sunday, the 28-year-old actor announced on Instagram that the Game of Thrones star "said yes" to his proposal, and amid numerous fan comments, Lovato had a congratulatory message.
"HUGE CONGRATS!!!!!" the 25-year-old singer wrote. "Sooooo for the both of you!!!!"
Selena Gomez -- Lovato's longtime pal and the ex-girlfriend of Joe's younger brother Nick -- also responded to the exciting news, writing: "Congratulations."
Meanwhile, Turner posted the same engagement photo to her Instagram, and got her own congratulatory comments from her famous friends.
"Congrats," supermodel Emily Ratajkowski wrote to the 21-year-old actress.
Sharing her surprise upon hearing of the proposal, Modern Family's Sarah Hyland later remarked, "GURL. WHAT?!?!?!"
In addition to all the ladies, Nick also reacted to his sibling being engaged, writing: "Ahh! Congratulations to my brother... and sister-in-law-to-be on your engagement. I love you both so much."
Here are more details on the newly engaged couple's romance, including what Turner recently told ET about her husband-to-be: