How many movies have Robert O. Cook and Robert Stevenson collaborated on?

They have worked on 13 movies together! Their first movie together was The Best Doggoned Dog in the World (1957) while their highest rated movie together was I Captured the King of the Leprechauns (1959). They have not worked together since Bedknobs and Broomsticks (1971). They are most known for their family films together.