My Sister The Weirdo

Justin Long

Alvin Seville (Voice)

Matthew Gray Gubler

Simon Seville (Voice)

Jesse McCartney

Theodore Seville (Voice)

Christina Applegate

Brittany Miller (Voice)

Anna Faris

Jeanette Miller (Voice)

Vanessa Bagdasarian

Eleanor Miller / Lucy/ Kate (Voice)

Ross Bagdasarian Jr.

Alvin Seville (Voice) / Simon Seville (Voice) / Dave Seville (Voice)

Janice Karman

Theodore Seville (voice) / Brittany Miller (voice) / Jeanette Miller (voice)

Vanessa Bagdasarian

Eleanor Miller (voice)

Michael Bagdasarian

Officer Dangus (voice) / Cheesy (voice)