How many movies have David Thwaites and Vin Burnham collaborated on?

They have worked on 2 movies together! Their first movie together was The Chronicles of Narnia: Prince Caspian & The Voyage of the Dawn Treader (1989) while their highest rated movie together was The Chronicles of Narnia: The Silver Chair (1990). They have not worked together since The Chronicles of Narnia: The Silver Chair (1990).