How many movies have Joey Murphy and Rolf Ernser acted in together?

They have worked on 4 movies together! Their first movie together was Teenies Extrem 20 (1989) while their highest rated movie together was Heidi 3: In der Heidi ist es doch am schönsten (1990). They have not worked together since Heidi 2: Im Wald und auf der Heidi (1990).