The main characters were:
* Charles Ingalls: The father of the family, a kind and hardworking man.
* Caroline Ingalls: The mother, a strong and resourceful woman.
* Laura Ingalls Wilder: The second oldest daughter, the main character of the books and TV series.
* Mary Ingalls: The oldest daughter, who later goes blind.
* Carrie Ingalls: The youngest daughter.
* Pa Ingalls: The patriarch, a skilled carpenter and farmer.
* Ma Ingalls: The matriarch, a strong and resourceful woman.
* Half Pint: The family's dog.
While the show featured many other characters, none were named Stacy. Perhaps you are thinking of a different show or a different character?