'Switched at Birth:' ABC Family Orders 22 Episodes

Ron Tom/ABC

ABC Family has given a back-season order of 22 episodes to hourlong original drama Switched at Birth, the net's president Michael Riley announced Monday.

The show will air its summer finale on Aug. 8 at 9 p.m., and return in early 2012.

Switched at Birth was ABC Family's most-watched series debut ever with 3.3 million total viewers (1.3 million in the key 18-49 demo) tuning in for its June premiere. Overall, the show was cable's No. 1 scripted telecast for the night among total viewers, adults 18-34 and adults 18-49.

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“Viewers have fallen in love with this show, just as we did when we first saw it,” says Riley in a statement “We set out this year to bring viewers more original content than ever before, all with the trademarks of our bright, authentic, quality storytelling. We’re so thrilled to see this series become a break-out hit this summer and become a key component of our programming lineup into next year.”

“Everything about this ground-breaking show speaks to our Millennial viewers,” says Kate Juergens, executive vice president, original programming & development at ABC Family. “It has heart, humor, drama and an incredible cast that has brought beautifully nuanced performances to every role. To see it resonate so deeply with audiences is just fantastic.”

Switched at Birth centers on two teenage girls who discover that they were swapped at the hospital shortly after their birth. The show stars Katie Leclerc, Vanessa Marano, Lea Thompson, D.W. Moffett, Marlee Matlin, Lucas Grabeel, Constance Marie and Sean Berdy.

Marie recently received an ALMA nomination for favorite TV actress in a supporting role.