Character Analysis
Wicked Stepmother?
Miss Amy is Joel's father's new wife, his stepmother. Though she doesn't really seem to have that much of a relationship with Mr. Sansom after all. Her primary relationship isn't with her husband, but rather with her cousin, Randolph. If that sounds a little creepy it's because it is; Randolph has a weird hold on Amy and can sort of control her.
We first meet Miss Amy as she murders a blue jay in Joel's bedroom while he sleeps, his first morning at the Landing. Nothing says "welcome" like slamming a bird with an iron poker to wake up a houseguest. Her cruelty isn't self-motivated, however; she gives the bird to Randolph, who likes to use dead birds to create cardboard models of birds. Yeah, like we said: cree-py.
Miss Amy is prone to fits or spells, or some other Southern euphemism for losing her mind. Whether it's screaming, "Snake a snake I thought it was a snake bit me crawled under the table bit me foot you fool never forgive bit me my heart a snake," (1.4.49) in response to Randolph's kicking her, or insisting it's her birthday because she "feel[s] as though it was [her] birthday" (2.11.9), Miss Amy is prone to losing touch with reality.
This might be due to the fact that her life is basically a lie. Randolph uses her to control Mr. Sansom and Joel; she's only married to Sansom in name, really, because she married him after he'd been shot by Randolph and paralyzed.
Miss Amy isn't cruel; she's weak. She isn't strong enough to stand up to Randolph, and so she goes along with his weird (or maybe wicked?) plans.