Heidi is a work of children's fiction published by Swiss author Johanna Spyri, originally published in two parts as Heidi: her years of wandering and learning and Heidi: How she used what she learned. It is a novel about the events in the life of a young girl in her grandfather's care, in the Swiss Alps. It was written as a book "for children and those who love children" (as quoted from its subtitle). Heidi is one of the best-selling books ever written and is among the best-known works of Swiss literature. Heidi is an orphaned girl initially raised by her aunt Dete in Maienfeld, Switzerland after the early deaths of her parents, Tobias and Adelheid (Dete's sister and brother-in-law). Dete brings 5-year-old Heidi to her paternal grandfather's house, up the mountain from Dörfli. He has been at odds with the villagers and embittered against God for years and lives in seclusion on the alm. This has earned him the nickname 'Uncle Alp'. He briefly resents Heidi's arrival, but the girl's evident intelligence and cheerful yet unaffected demeanor soon earn his genuine, if reserved, affection. Heidi enthusiastically befriends her new neighbors, young Peter the goatherd, his mother, Bridgget, and his blind maternal grandmother. With each season that passes, the mountaintop inhabitants grow more attached to Heidi. Three years later, Dete returns to take Heidi to Frankfurt to be a hired lady's companion to a wealthy girl named Clara Sesemann, who is regarded as an invalid. The girl is charmed by Heidi's simple friendliness, and delights in all the funny mishaps brought about by Heidi's lack of experience with city life. However, the Sesemanns' strict housekeeper, Fräulein Rottenmeier, views the household disruptions as wanton misbehavior, and places Heidi under more and more restraint. Soon, Heidi becomes terribly homesick, and grows alarmingly pale and thin. Her one diversion is learning to read and write, motivated by her desire to go home and read to Peter's blind grandmother. Clara's paternal grandmother comes to visit the children and becomes a friend to Heidi. She teaches Heidi that she can always seek relief from misery by praying to God. After months pass, the Frankfurt household is brought near hysteria by nightly sightings of what appears to be a ghost. When Clara's father and his friend the doctor keep awake one night to find out what is causing the disturbances, they see that the "ghost" is actually just Heidi, who's sleepwalking in her nightgown. The doctor sees that Heidi's under a great deal of stress. He warns Mr. Sesemann that if Heidi is not sent home promptly, she may become very ill. Soon, a joyous Heidi returns to the mountains, where she teaches her grandfather about the comfort of prayer. She reassures him that it's never too late to turn back to God. Her simple lesson prompts her grandfather to descend to the village and attend a church service for the first time in years, marking an end to his seclusion. He's heartily welcomed back by the church pastor and the villagers.