Vater sein dagegen sehr is a 1957 West German film directed by Kurt Meisel.
Lutz and the children become good friends. The children want to stay with their uncle, but he does not have much room in his tower apartment, has little money, and wants to get married soon.The children must return to the Roeckel family, but they run away, because there is always trouble there. The softhearted uncle takes them in, but his fiance has definite ideas about their future, and they dont include other peoples children. On the spur of the moment, she tells him that she no longer wants to marry him. ........
Source: Wikipedia