Alec Baldwin

as Theodore Templeton (voice)

James Marsden

as Tim Templeton (voice)

Amy Sedaris

as Tina Templeton (voice)

Ariana Greenblatt

as Tabitha Templeton (voice)

Jeff Goldblum

as Dr. Armstrong (voice)

Eva Longoria

as Carol Templeton (voice)

James McGrath

as Wizzie (voice)

Jimmy Kimmel

as Ted Templeton (voice)

Lisa Kudrow

as Janice Templeton (voice)

Raphael Alejandro

as Nathan / Lead Baby Ninja (voice)

Serenity Reign Brown

as Meghan (voice)

David Soren

as Jimbo (voice)

Nicholas Gist

as The Triplets (voice)

James Ryan

as Story Bear (Connie) (voice)

David P. Smith

as Movie Patron (voice)

Nova Reed

as Little Bo Peep Baby (voice)

Molly K. Gray

as Creepy Girl (voice)

Ashlyn Lundahl

as 'No' Girl (voice)

Dave Needham

as Glue Baby (voice)

Tom McGrath

as Dr. Tiffany Hamilton (voice)

Reyn Doi

as Box Kid (voice)

Collin Erker

as Time Out Kid (voice)

Walt Dohrn

as Baby Bouncer (voice)

April Lawrence

as Acorn Center Computer (voice)

Miles Bakshi

as Young Tim Voice-Over (voice)

Kristin Lowe

as Pageant Mom 1 (voice)

Marjorie Cohn

as Pageant Mom 2 (voice)

Connor Albrecht

as Dreidel Kid (voice)