Peter Horton and Cynthia Stevenson to Guest Star on Life Unexpected

Life Unexpected is yet to premiere, but the buzzed-about CW series has already landed its first impressive set of guest stars.

Peter Horton, best known for his extended run on thirtysomething, will play Cate Cassidy's father on the series. The veteran actor was mostly recently seen in In Treatment and Brothers & Sisters.

Cate's mother, meanwhile, will be portrayed by Cynthia Stevenson. The actress had a key role on Anne Heche's Men in Trees and actually guest stars on tonight's episode of Grey's Anatomy. She'll debut on the third installment of Life Unexpected.

Tweeted series creator Liz Tigelaar:

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