How many movies have Kathleen Warners and Wilbert Hietbrink collaborated on?

They have worked on 6 movies together! Their first movie together was Micha Wertheim: Voor Beginners (2006) while their highest rated movie together was Micha Wertheim: Voor Gevorderden (2008). They have not worked together since Micha Wertheim: Voor Zichzelf (2016). They are most known for their comedy films together.