The Photographer by Mary Dixie Carter
Delta Dawn carefully creates perfect memories of children's parties even when she has to tweak the images a bit to get the effect she wants. She's worked hard distance herself from her own childhood and to make herself blend in with her clients. After photographing little Natalie Straub's party, Dawn realizes that she wants to become part of their perfect family and starts working to make that happen, first offering to babysit, then gradually making herself indispensable to the family.
A single sentence early on reveals that Delta isn't the nice young woman she presents herself as. She's not particularly likeable, but she's definitely fascinating to read about as she puts her plan in motion.
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