K-Fed Celebrates TV Debut

Among those millions of viewers who caught Kevin Federline’s debut on One Tree Hill last night was K-Fed himself.

Sources tell OK! that the 29-year-old threw a bash at his Tarzana, Calif., home in honor of his small-screen success.

“He had a bunch of friends over to celebrate and watch his TV debut on One Tree Hill,” a source tells OK!.

Guests included Kevin's bodyguards, record producers, his studio engineer Zach and other close friends, who dined on take-out and pizza during a viewing of The Last King of Scotland before the 9 p.m. broadcast of the episode. When the minute hand neared the hour, the former rapper made sure his biggest fans were present -- sons Sean Preston, 2, and Jayden James, 1.

"Kevin went upstairs and brought the kids down to play beside him," the source says. "He said to the kids, 'You wanna see daddy on TV?' And the kids were excited."

When his name appeared on screen, the room erupted in a loud cheer, the source adds, but support soon turned into teasing as, halfway through the episode, Kevin still hadn't graced the screen as Jason, the lead singer of a rock band discovered by aspiring record label owner Peyton Sawyer (Hilarie Burton)..

"They joked, 'Are you sure they didn't just use your name to boost ratings because of all the BS BS (Britney Spears b.s.) and you ain't really in it?'"

But before long, Kevin finally appeared on screen rocking out, and immediately "grabbed Sean Preston and pointed at the screen saying, 'Look - daddy!' and Sean responded, 'Daddy!' As soon as Jayden heard Sean speak, he responded, 'Dada' and he clapped repeatedly," the insider says.

While his sons were proud of their daddy, Kevin was overcome with self-consciousness at his appearance, asking, "Do I look a little chubby?", to which his friends admitted he was carrying a little belly weight. (Remember the camera adds 10 pounds, Kevin!).

"You could tell Kevin was very anxious as to what his friends thought," the source says. "Everyone had in the room commended him on his performance. He asked if that image worked for him. One of his friends responded with, 'If the music is hot, it does not really matter what you look like. You fans will love you.'"

However the praise may have just been out of consideration -- one partygoer felt his performance was "kind of weak," but refrained from saying so as to not burst his bubble.