The Ingalls clan experiences joy and strife on the American frontier in this release featuring all 22 episodes of Little House on the Prairie: Season 4. Season four of Little House on the Prairie finds the Ingalls' household increased from five to six after Caroline Ingalls (Karen Grassle), wife of series protagonist Charles Ingalls (Michael Landon), gives birth to another daughter, named Grace. At the same time, the Ingalls' farmer friend Isaiah Edwards and his family leave Walnut Grove (Victor French, the actor playing Edwards, had gone off to star in his own sitcom, Carter Country), whereupon the town greets a new crop of citizens: kindly but bull-headed farmer Jonathan Garvey (Merlin Olsen), his wife, Alice (Hersha Parady), and their troublesome son, Andy (Patrick Laborteaux). That said, it must be emphasized that most of the season's meatier plotlines are focussed on the Ingalls' household. Inspired by her teacher, Miss Beadle (Charlotte Stewart) -- who gets married in the course of the season -- Mary Ingalls (Melissa Sue Anderson) opts for a teaching career herself. Alas, it looks as if her ambitions may be dashed when Mary is told that she is going blind. Once she has reconciled herself to her fate -- but is still determined to make education her life's work -- Mary agrees to attend a blind school in Winoka, Dakota Territory, where she meets and falls in love with her new teacher, Adam Kendall (Linwood Boomer). Season five marks the final full season in which Karl Swenson appears in the role of mill owner Lars Hanson; the actor passed away in the fall of 1978.