S8, E1: Percival takes over the family business when his father dies, which means that he and Nellie will remain in New York permanently. Distraught by the news, Harriet and Nels decide that adopting a little girl would make them happy, but when they visit the orphanage, Harriet gravitates to the most unruly. Meanwhile, Adam struggles to make a living as a lawyer in Walnut Grove.