Peter is the bearer of bad news when he learns that Heidi's favourite goat is going to be sacrificed after the summer because it doesn't provide with enough milk. Heidi gets devastated by the news and her grandfather's words won't put her at ease. After having a nightmare at night, Ohi advices her to feed the goat with a particular kind of herb that could save the animal's life. Peter and Heidi spend the whole summer doing so.