The new baby joins Enrique Iglesias and Anna Kournikova's 2-year-old twins, Lucy and Nicholas

Nicholas and Lucy have a little sister!

Enrique Iglesias and Anna Kournikova welcomed their third child together on Thursday, Jan. 30, the singer announced Thursday on Instagram.

“My Sunshine,” the new dad of three captioned a photo of himself in the hospital holding his newborn daughter, who’s sporting a beanie topped with a bow.

The couple’s baby girl joins Lucy and Nicholas, the 2-year-old twins Kournikova, 38, and Iglesias, 44, welcomed in December 2017. They were the first children for both the singer and former pro tennis player, who have been together for almost two decades.

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Enrique Iglesias welcomes baby
Enrique Iglesias, Anna Kournikova and their newborn daughter
| Credit: Anna Kournikova/ Instagram

After the twins were born, a source told PEOPLE that she and Iglesias had been “keeping [the pregnancy] very, very undercover.”

While the couple don’t often open up about one another (or share a ton of photos of their twins on social media), Kournikova told Women’s Health in 2011 that kids were definitely on her agenda — but marriage wasn’t a priority.

“I absolutely want to have children, whether I have my own or adopt,” said the Russian retired athlete, adding, “I love taking care of people.”

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Continued Kournikova, “[Marriage] isn’t important to me. I’m in a happy relationship — that’s all that matters … I believe in commitment. I believe in being open and trusting each other and respecting each other completely.”

The “Escape” singer told PEOPLE en Español in 2007, “The only thing I can say is that, in my opinion, Anna, whether we are together or not, would be an ideal mother.”

“I think she’d be the perfect mother, and I say it regardless of whether I’d be with her or not,” added Iglesias of the former The Biggest Loser trainer.