On Thursday, the “Wolves” singer, 25, shared a cute snap of herself laughing and pointing to a photo of Bieber to celebrate his big day.
“March 1, 1994 someone I know that happens to be super cool was born. Boom,” she captioned the photo, which was shared with her 134 million followers.
Gomez also posted — then quickly deleted — a photo of blue and black balloons with a silver “24” Mylar numbers that also included a wall of Polaroid selfies of the pair.
Bieber, 24, and Gomez reunited shortly after she split from singer The Weeknd in October. Though she’s stayed mostly mum on their reconciliation she told Billboard in November that she holds Bieber close to her heart.
“I’m 25. I’m not 18, or 19, or 20,” she told the outlet. “I cherish people who have really impacted my life. So maybe before, it could have been forcing something that wasn’t right. But that doesn’t mean caring for someone ever goes away.”
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Though they’ve certainly had their ups and downs through the years, the couple — who first began dating in 2010 — have been going strong this time around.
“Their relationship is very special. They have both changed, their lives are so different and it really seems things could work out great this time,” a source previously told PEOPLE. “Justin realized that he needed to change, reached out for help and is doing very well.”