Hurra, ich bin Papa (1939)

Peter Ohlsen, a perpetual student, leads a dissolute life and has been living off his filthy-rich father for years. When Peter comes home drunk from a party with his friends yet again, he finds a three-year-old boy in his bed who had been left with his housekeeper along with a letter. The letter states that Peter is the boy’s father and that he is hereby entrusted with the child’s upbringing.