How many movies have J.K. Rowling and Stephenie McMillan collaborated on?

They have worked on 8 movies together! Their first movie together was Harry Potter and the Philosopher's Stone (2001) while their highest rated movie together was Harry Potter and the Deathly Hallows: Part 2 (2011). They have not worked together since Harry Potter and the Deathly Hallows: Part 2 (2011). They are most known for their adventure films together.