Seth MacFarlane Sings Frank Sinatra, Robert Pattinson and Nina Dobrev Attend Ted 2 Bash

Seth MacFarlane threw a star-studded bash for his upcoming comedy Ted 2 on Thursday, June 19 Credit: Gregg DeGuire/WireImage.com

Mandy, Tiffany, Candace, and Brandy showed up, too — right!? Seth MacFarlane threw a star-studded bash for his raunchy new comedy, Ted 2, at his Beverly Hills home on Thursday, June 19. The Family Guy actor hosted celebs like Robert Pattinson and Nina Dobrev, and even belted out some Frank Sinatra tunes onstage.

An insider exclusively reveals to Us Weekly that Victorious star Elizabeth Gillies covered "I've Got the World on a String," and was followed by MacFarlane singing "Learnin' The Blues" and "The Love Boat" for the packed house.

The private bash had several bar areas, a sushi booth, and a smoking section, the source notes. Attendees mingled poolside, noshed on appetizers and desserts, and were entertained by a jazz band and DJ. MacFarlane took it upon himself to also transform his tennis court into a jazz bar, and an upper deck stocked with alcohol was built specifically for the festivities.

But it gets even better. Guests, including his Family Guy costar Alex Borstein, Geoff Stults, Ben Savage, Dennis Haysbert, Debby Ryan, and Dobrev's new boyfriend, Whiplash star Austin Stowell, were driven up to his pad in golf carts after checking in with the valet. Near the entrance, a photo booth was set up with naughty props, bongs, alcohol bottles, and (behold!) a stuffed animal Ted.

"How many of you came to the screening? How many of you came just to the party?" MacFarlane, 41, asked the crowd at one point. He joked: "You motherf—kers!"

Dressed casually in jeans and a dark gray button-up, the host made the rounds at the shindig, and stopped for a bit to talk with hunky Pattinson, who chatted with The Cheetah Girls' Sabrina Bryan.

Dobrev later joined Pattinson with a group of friends, but kept close with Stowell for most of the night. They kissed and danced, the source says.

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