Suggestions by @cooperthedal

Caleb Paddock

as Grandson in The Princess Bride

Matthew Paddock

as Arthur in The Sword in the Stone

Griffin Gluck

as Ron Stoppable in Kim Possible

Jared Gilmore

as Ron Stoppable in Kim Possible

Ethan Cutkosky

as Ron Stoppable in Kim Possible

Julia Louis-Dreyfus

as Dr. Ann Possible in Kim Possible

Mark Wahlberg

as Dr. James Possible in Kim Possible

Francesca Capaldi

as Kim Possible in Kim Possible

Raffey Cassidy

as Kim Possible in Kim Possible

Angourie Rice

as Kim Possible in Kim Possible

Danny DeVito

as Mike Wazowski in Monsters, Inc.

Caleb Paddock

as Jim Possible in Kim Possible

Matthew Paddock

as Tim Possible in Kim Possible

Alyson Stoner

as Kim Possible in Kim Possible

Emily Rose

as Murphy in The Dresden Files

Casey Affleck

as Dallas in Alien

Sean Astin

as Newt Hoenikker in Cat's Cradle

Nathan Fillion

as Taiyang Xiao Long in RWBY

Natalie Dormer

as Glynda Goodwitch in RWBY

Natalie Dormer

as Yang Xiao Long in RWBY