Anderson Cooper Host 'Jeopardy!' While Toddler Son, Wyatt, Watches

Who said nerds aren't sexy?

CNN news anchor Anderson Cooper hosted the first day of his two-weeks as guest host on Jeopardy! this week, and his excitement was palpable.

"Tonight is the first night I guest-host on Jeopardy!" he wrote on Instagram. "I rarely get nervous, but I definitely was the first moment I stood behind Alex Trebek's podium. It was a great honor and very moving for me."

In a behind-the-scenes video, Cooper explained that he's loved the show for decades. "I love Jeopardy! I've been watching since I was in high school," he said. "I'm a huge fan of Alex Trebek, so to be here and be able to pay tribute to him and his extraordinary life and career, raise money for some great causes, and also just to meet these brilliant contestants is such a thrill."

He also revealed that he was able to talk to Trebek shortly before he died. "I got a call from him about a month or two before he died, and he was asking me about some other stuff, but I used it as an opportunity to say to him how much I appreciated him, how much he had brought to my life and the life of so many people," Cooper said. Between Trebek's death and the naming of another permanent host, the show has scheduled a slate of guests.

Guest hosts have been able to choose a charity and the show has been matching the dollar amounts won by contestants on their episodes and donating the amounts. Cooper chose Hopital Albert Schweitzer Haiti, a hospital and four community health centers in Haiti. For his second week of hosting, he chose Justice Defenders, an organization that provides lawyers to those who can't afford them in East Africa.

He also posted an absolutely adorable picture of his son Wyatt watching him host the show on Instagram. Cooper is co-parenting Wyatt with his ex. "Wyatt had never seen me on tv before, and he likely won't for a long while, but apparently he caught a bit of me on @Jeopardy!" he wrote. "It was a dream come true to be guest hosting, and to pay tribute to Alex Trebek and raise money for Hopital Albert Schweitzer Haiti."

Cooper took over hosting duties from Green Bay Packers quarterback Aaron Rodgers, and will be followed up by 60 Minutes correspondent Bill Whitaker. Other guest hosts will include actress Mayim Bialik, Today anchor Savannah Guthrie, and CNN chief medical correspondent Dr. Sanjay Gupta. A permanent replacement for Trebek has not been announced.

Cooper has been a contestant four times before winning twice.

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