Britney Spears wished Madonna a happy 55th birthday via Instagram on Friday, Aug. 17 by sharing a 2003 VMAs throwback photo of the two Credit: britneyspears/ Twitter

Old school moment! In lieu of celebrating Madonna turning 55 on Friday, Aug. 16, Britney Spears shared a throwback picture of the two women backstage at the 2003 MTV Video Music Awards -- the show that led to the infamous kiss between the pop queens. 

"Happy Birthday M!!! Hope you're a happy girl. Singing you your birthday song :) Xo," the 31-year-old wrote via Instagram. The caption was accompanied by the photo that showed the "Ooh La La" singer in her white wedding gown costume and the "Gimme All Your Love" singer sporting her black attire sans the top hat.

The stars made headlines ten years ago when Madonna played the groom to Britney Spears and Christina Aguilera's brides in the opening act for the music award show. All three danced and sang to Madonna's 1984 classic "Like A Virgin" plus the 2003 single "Hollywood."

This isn't the first time either Spears or Madonna have referenced back to the VMA performance. The "Hung Up" star tweeted about it after the "Hold It Against Me" star congratulated her on her new album, MDNA, in April 2012.

"Love the new album -- every single song is incredible. Congrats girl!" Spears wrote at the time. "Please come on stage and kiss me again. I miss you!!" Madonna replied.