The 29-year-old rapper and the singer, who duet on "Him & I," had broken up early this summer following a one-year relationship. A month ago, they showed PDA onstage and on Instagram, signaling a reconciliation.
"Happy birthday to this one," G-Eazy wrote on Instagram on Saturday. "I love you so so so much and I always will."
The two began their trip to Italy earlier this week. The rapper shared three photos from their visit—two of Halsey posing and one of him and the singer embracing while standing in front of a private jet. A day earlier, both he and Halsey had posted on their Instagram Stories videos taken on a gondola ride in one of the city of Venice's many canals.