Millie is an elderly woman who had hired Blanca Flores as a live-in carer before her incarceration. She appears solely in Flores' flashbacks in "Turn Table Turn". She is portrayed by Mary Louise Wilson.
Millie is first seen yelling for Blanca (whom she calls "Bianca") whilst Blanca showers. Reluctantly, Blanca makes her way downstairs after changing and drying. Millie explains to Blanca she is hungry, and needs to eat. Blanca takes soup and makes her way to the microwave, before Millie yells at her and tells her to heat it up on the oven. Millie explains to Blanca that she received a call from her daughter, Margaret. Millie explains that she is content with staying with Blanca as opposed to being forced into a home under Margaret's wishes.
After Blanca meets Diablo, the two start a relationship. Blanca and Diablo work together in the house and talk in Spanish. Millie tells them that she cannot understand what the two are talking about, and that it is rude. Blanca and Diablo put Millie in the car, the two keep talking for several minutes. Millie gets impatient and tells them to hurry up.
Millie and Blanca sit on her balcony doing a jigsaw. Millie is disappointed in Blanca for not finding a piece of the puzzle. Blanca notices a brand new gardener has been set in place of Diablo. Millie explains she fired him because she didn't like the way Blanca and Diablo were behaving. Millie explains she has to urinate. Blanca takes her away, it looks like for a second Blanca was going to push Millie off the balcony, but Blanca takes her away instead.
Late at night, Millie is disrupted in her sleep. She awakens to find Diablo and Blanca having sex loudly. Due to Millie not being able to walk or move, she is forced to watch and listen. ("Turn Table Turn")
It is unknown what happened to Millie after this.