Ich liebe meine Familie, ehrlich (1999)

The journalist Julia Schiller has kicked out her faithless husband Wolf, but her teenage daughters Anna and Lena and the cheeky twins Anton and Philipp keep her busy. When her sprightly aunt Isolde starts working as a hobby detective on the trail of a poisoner in her retirement home, the children sense an adventure and help her. But then Isolde suddenly disappeared too. Julia is very worried and asks Wolf for help again.