Kleine Sünder – große Sünder (1966)

Originaltitel: Min søsters børn

Erik Lund is a child psychologist and defend a doctoral thesis on the subject. His knowledge is at the very theoretical level, and he will be seriously trouble when he for a time has to babysit his sister's six children ranging in age from baby to teenager. Fortunately, the neighbor cute daughter, Lisbeth has a more practical take on things.