Invalid Klara comes from a wealthy family in an anonymous city far from the mountains. Her father, a businessman, is often away, leaving Klara to be raised by strict governesses, notably Miss Rottenmeier.
Though her condition is never given a specific modern name, the Swiss mountain air miraculously allows Klara to regain her strength and eventually walk again.
Initially sheltered, lonely, and lacking in confidence, Klara transforms into a braver, much more optimistic person thanks to Heidi's energetic and compassionate nature. In return she helps Heidi discover her bi-curious side.