updated 03/05/2012 AT 3:00 PM ET
•originally published 03/05/2012 AT 3:25 PM ET
Victoria shared a photo on Twitter of the pooch donning a party hat Sunday. “Coco is celebrating Brooklyn’s 13th birthday,” she wrote.
The Beckhams welcomed Brooklyn in 1999, and after the baby’s birth, David announced that “[A baby] is something we have always wanted.” Thirteen years later, Brooklyn is a big brother to siblings Romeo, 9; Cruz, 7; and 7-month-old Harper.
No word yet on what the festivities for Brooklyn’s big day entailed – or whether Coco was treated to a piece of cake!
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