WATCH: Victoria and David Beckham celebrate Romeo's 18th with unseen family photos
"Happy birthday @romeobeckham X kisses on your birthday!! Love you so much @brooklynbeckham @cruzbeckham #HarperSeven," gushed doting mum Victoria alongside a snap of her four children standing next to the delicious sweet treat.
Fans of the fashion designer were quick to comment, with one writing: "Love the rainbow cake." Another remarked: "Happy Birthday Romeo. Love the cake."
Earlier on in the day, Victoria - who is also a mum to Brooklyn, 21, Cruz, 15, and nine-year-old daughter Harper - shared a montage of never-before-seen photos of Romeo with his loved ones. "Happy 18th birthday @romeobeckham... We couldn't be prouder of the young man you have become," she wrote in the caption. "You are beautiful inside and out and we love you so much. The sweetest, kindest soul, our everything. So many kisses from us all xxxxx."
A snap of Romeo's birthday cake
David, 45, added: "Happy 18th to my little man (or not so little anymore). You have grown into the most beautiful person and that as you say yourself (a man finally) we love you so much never give up on your dreams and goals.
"This shows from day one in my arms with the song you were born to up until our latest moment where yes I had to finally admit my son is taller than me. Happy Birthday mate."
Romeo's model girlfriend Mia Regan also paid tribute to the teenager, writing: "Happy 18th my gorgeous boy man!!!!! You have the most beautiful soul and deserve everything. YOU MAKE EVERYONE SMILE AND I LAVAAA YOOU SO MUCH." [sic]
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