Need To Know: Jimmy Fallon Makes Money On 'Tonight Show' Debut

Simon Cowell and John Krasinski become first-time fathers, while Pete Wentz announces he'll be a dad for the second time.

Jimmy Fallon made his debut as host of "The Tonight Show" on Monday and packed in an impressive number of surprise guests. While Fallon got used to hosting, Simon Cowell and John Krasinski were on diaper duty. Here are today's top stories.

Jimmy Fallon Spews Charm, Makes Money On 'Tonight Show'

Fallon took over "The Tonight Show" hosting duty on Monday and, unsurprisingly, did not disappoint. Backed by The Roots, the comedian let loose with guests U2 and Will Smith (who performed an impressive "Evolution Of Hip-Hop Dancing" with Fallon), plus a slew of others, including Mariah Carey, Lady Gaga and Lindsay Lohan, who stopped by to pay their respects... oh, and $100 they owed after betting Fallon that he would never host "Tonight."

A Big Weekend For Babies

Presidents' Day weekend turned out to be a big one for babies. Simon Cowell tweeted some sweet snaps of new son Eric, saying "I never knew how much love and pride I would feel." John Krasinski and wife Emily Blunt welcomed daughter Hazel in to the world on Sunday. And Pete Wentz, father to 5-year-old Bronx Mowgli with ex Ashlee Simpson, announced via Instagram that he and model girlfriend Meagan Camper are expecting. Congrats to all the happy couples.

Charlie Sheen Stops Ranting To Propose

The actor took a break from tweeting obscenities about "Two and a Half Men" successor Ashton Kutcher to propose to his 24-year-old girlfriend over the weekend. Brett Rossi, a porn-star-turned-nurse, accepted Sheen's Valentine's Day proposal with a paparazzi photo shoot on a tropical beach. This will be the fourth marriage for Sheen.

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