Who is Miss Amy from Other Voices, Other Rooms and what is their importance?

Miss Amy is the first person Joel encounters at Skully's Landing, as she attempts to catch a bird flying in Joel's bedroom. Miss Amy is married to Joel's father, Edward Sansom, who is the victim of an accidental shooting by Randolph. Amy comes to Randolph's aid after the shooting and nurses Edward's wounds, eventually marrying Edward so that she'll have someone to care for forever. Miss Amy brings Edward and Randolph back to her family's home to live at Skully's Landing and the threesome becomes an eccentric family unit. Even though it had been Miss Amy who had done Randolph the favor of helping the wounded Edward and bringing him to her home, Randolph maintains a powerful control over Miss Amy, making all the major and minor decisions for the household. Miss Amy is responsible for managing the house and Edward's care while also ministering to Randolph's petulant, drunken needs and enduring his cruel behavior toward her. Miss Amy had hoped that Joel's residence in the house would alleviate some of her daily responsibilities for Edward, but Joel wants nothing to do with Edward's care. This shirking of duty combined with Randolph's growing love for Joel make Joel a source of disdain for Miss Amy, who originally held out hope for a mutually beneficial relationship with Joel.