Nicky Hilton Rothschild's baby boy is here!
On Tuesday, the fashion designer, 38, announced the arrival of her third baby with husband James Rothschild on Instagram.
"We are officially a party of 5!" she wrote, sharing a black-and-white silhouette image of the proud parents. "Welcome to the world sweet boy. Mom, dad and big sisters could not be more smitten. 💙"
The couple hasn't shared the baby's date of birth or any further details at this time.
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The pair laid poolside in matching swimsuits with their baby bumps on display in the pictures.
"Suns out ☀️ Bumps out 🤰," Nicky captioned the post. "Can't wait for the cousins to meet each other! 🥰."
In May, Hilton Rothschild celebrated her baby on the way, a boy, with an all-things blue baby shower. She shared moments from the festivities in an Instagram carousel, beginning with a photo of her holding her baby bump as she posed with sister Paris Hilton.
"Showered with so much love at baby boy's sprinkle.🧸💙🍼," Nicky captioned the photos, which ended with Lily-Grace and Teddy indulging in sweet treats. One snap showed an adorable girl hiding under a life-size teddy bear.
The same month, mom Kathy Hilton predicted it wouldn't be long until she was traveling to New York for the arrival of her grandson. "Nicky is easy. I fly in [to New York] for all the births," she told PEOPLE. "I'll be there holding her hand. It'll be in the next five or six weeks."
PEOPLE confirmed in January that Nicky and her husband of nearly seven years were expecting their third child together.