Patrick Kielty and Cat Deeley attend Dior and Maxfield Celebrate the Launch of Winter 2014 Dior Fusion Sneaker Collection. Credit: Donato Sardella/WireImage

Cat Deeley and her husband, Patrick Kielty, have welcomed their first child! The So You Think You Can Dance host, 39, shared the news with her fans on Twitter on Tuesday, January 19.

“Beyond delighted to announce the birth of our baby boy last week. All doing well & we couldn't be happier... 3 really is the magic number!” she wrote.

The TV personality and model first revealed her pregnancy in September on Twitter.

"Exciting news....Paddy and I are so happy to be expecting our first child in the Spring....." she wrote at the time. "Lucky us."

Weeks later, Deeley attended the Emmy Awards in a revealing gold gown that showed off her growing baby bump.

“I managed to squeeze myself in this Monique Lhuillier gown, and we had to let the back out a little bit, but the rest is OK!” Deeley told Giuliana Rancic on the red carpet. “I’m hanging in there.”

The couple wed in a Rome ceremony in 2012. 

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