Good Luck Charlie - Jason Dolley Good Luck Charlie - Jason Dolley

Remember the TGIF sitcoms of yesteryear? Jason Dolley does, and he's not quite sure what happened to them.

"They were so huge, especially when my parents were growing up — everyone watched TV together," he tells of such classic Friday-night family comedies as The Brady Bunch and The Partridge Family. "That whole TGIF concept, for whatever reason, is gone now. But I think we will sort of fill that void."

Dolley stars in the new Disney comedy Good Luck Charlie (premieres Sunday at 8:30/7:30c), a throwback to those old-school family sitcoms that appealed to multiple generations (think Step by Step and Family Matters). The series focuses on the Duncan siblings, P.J. (Dolley), Teddy (Bridgit Mendler) and Gabe (Bradley Steven Perry), who must care for their baby sister Charlotte ("Charlie") when their parents — played by Leigh-Allyn Baker and Eric Allan Kramer — return to work. 

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The premise sounds basic enough, but the show is a departure for the network, which in recent years has found success with more high-concept programming (Hannah Montana

, Wizards of Waverly Place, J.O.N.A.S., Sonny with a Chance)."When I read [the script], I was like, 'Oh, this is kind of cool. This is a little different,'" Dolley, 18, says. "It has a Full House kind of feel. It's very family-friendly. Families can sit down and watch this and get a real laugh. I think that's what's been cool about it from the start and what's still cool about it today."Dolley, who started acting at age 11, is no stranger to Disney, having starred in its TV movie Hatching Pete and on the short-lived series Cory in the House. Charlie, though, gives him the chance to play an "older, more grown-up, realistic" character.Older, but not wiser. "P.J. is best described by his little brother — he's not very 'thinky,'" Dolley says. "He's not the smartest guy in the family, but he's not dumb. He's super-nice. He's sort of a ladies' man too — very suave. He's a wannabe rocker. He loves to play the guitar, but he's not super-good."While P.J. is the oldest of the Duncan clan, Dolley is the youngest of four boys in real life, which gave him an "interesting" perspective. A large age gap meant his two oldest half-brothers never picked on Dolley and his brother, Jeffrey. The same can't be said for the Duncan siblings.

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"They're definitely more typically antagonistic, which is something I have to learn how to do!" he says. "We never really fought. ... Also, I don't know what it's like having a sister. I guess not having one, I treat girls a lot more gently than I would a guy. So the idea of picking on a girl, I'm like, 'That's kind of messed up!'"Though he's not familiar with sibling rivalry, Dolley knows most viewers will be able to relate to the Duncans' tiffs — and having to babysit a younger sibling. "P.J. is kind of a last resort as a babysitter! Most of the time, he's not stuck with the baby," Dolley, who babysits his brothers' kids, says. "There are situations where he's forced into taking care of her, but there are other situations where he volunteers — now that's for a different reason, which you'll find out. You do see him learn how to take care of the baby over the season."Viewers will also see Charlie take her first step and a "very cool" ice-dancing story line."There's lots of fun stuff coming up. I have no idea how the season is going to end. I think there's potential for a cliff-hanger with relationships and stuff like that," he says. "I don't think that's the way they're going to go with it right now. ... If we do have a cliff-hanger, hopefully we'll be back! I think people will respond to the show. Family sitcoms are definitely missing and missed."