This episode page has been compiled from the episode description at the NDR website.
Moni are sorting photographs while Lena are playing in the sandbox and suddenly she says "Mama", Moni are excited and wants to tell everybody. She carrries Lena over to Pepe but he are not home, she then spots Annette. Moni hurries and asks Annette if she can guess what have happened, Annette makes a guess but don't get answer because Moni notice Finchen and hurries over to the leafpile. Moni tells both Annette and Finchen that Lena have said "Mama".
Back at the sandbox, Moni decides to get her video camera to record it. Meanwhile Annette and Finchen tries to make Lena say "Mama" again, with no success. Finchen ends up concluding that maybe Lena don't feel like saying "Mama".
Annette believes that music are very inspiring and that it could make Lena say "Mama". Annette plays a little on the piano, but that did not make Lena say "Mama". Annette starts to sing "Mama", Finchen and Moni quickly joins in, but that have no effect either, after one more try Moni decides that she could might as well put away the camera. Then Lena says "Mama", Finchen, Annette and Moni cheers and they all start to sing again.