Dimitrios Kambouris/WireImage.com 1 / 20
Dimitrios Kambouris/WireImage.com 1 / 20

Nick Lachey tweeted a heartfelt message Monday about welcoming his son, Camden John, last Wednesday with his wife, Vanessa Lachey.

PHOTOS: Vanessa's maternity style

"Officially in cheesy dad mode," the "Sing-Off" host, 38, confessed. "Camden is easily the most amazing thing that has happened in my life. Vanessa Lachey and I are truly blessed!"

"We are incredibly proud to announce the birth of our beautiful baby boy, Camden John Lachey," the Lacheys, who wed in July 2011, told Us Weekly in a statement early Thursday. "Born today at 6:54 pm. He came into this world at 8lbs 9oz and 21 inches. Love has truly been redefined for both of us." 

PHOTOS: Nick and Vanessa's hot bodies

Nick's loving tweet Monday was the first time he spoke about his son's birth to his followers. New mom Vanessa has taken a break from Twitter since Camden's arrival.

PHOTOS: Nick and Vanessa's most romantic moments

Over the summer, Nick opened up to Us about all the changes he and Vanessa had gone through in the past year. "You get married, you get pregnant, and it all kind of happened so fast," he said. "But it's very exciting!"

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