Based on

Movies like Geheimnis einer Ehe (1951)

Tina Camphausen has three children, Christian, Schwänchen and Musi, who has grown up for 15 years without a father. The family leads a peaceful life together with Paul, the woman's partner whom the children have accepted. Cohabitation is tested when Felix makes his appearance, Tina's childhood friend and Christian's probable biological father.