The former tennis star posted an adorable snap that featured Enrique and their three children, twins Nicholas and Lucy, four, and two-year-old Mary. In the photo, the singer plants a kiss on Lucy while little Mary is sitting on his shoulders and Anna and Nicholas look on smiling.
WATCH: Anna Kournikova shares cute video of her children
Captioning the happy family photo, Anna penned: "Happy Birthday to the most amazing Dad! We super love you!!!"
Fans were quick to react, with many sharing their delight over "finally" seeing a photo of the family of five all together. "Finally, a family photo," replied one fan on Instagram. A second echoed the statement, adding: "Finally a family pic."
A third said: "Omg family piccc on Enrique's bday! LOVE YOU GUYS SO MUCH."
Anna finally shared a family photo to mark Enrique's birthday
The happy couple, who met on the set of Enrique's Escape music video, have been together since 2001 and welcomed their children without publicly announcing any of Anna's pregnancies.
They welcomed Lucy and Nicholas in 2017 and the birth was confirmed by HELLO!'s sister publication HOLA! just a few days after their arrival into the world. They revealed Mary's birth with a post on Instagram shortly after it was revealed that the couple were expecting a third child after HOLA! exclusively published photos of Anna's bump.
Despite their long relationship, it appears marriage is not yet on the cards. Asked about the prospect of tying the knot back in 2017, Enrique told The Sun: "I've never really thought marriage would make a difference.
"Maybe it's because I come from divorced parents, but I don't think you love someone more because of a piece of paper. And nowadays it's not taboo to have kids and not be married. What makes a difference is that you're a good parent."
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