Möjligen Margaret Peterson Haddix 2007 bok, Dubbelidentitet ?
Bethany Cole lives a normal life until her parents, Walter and Hillary, abruptly ditch her, where she is introduced to her aunt, Myrlie Wilkers, whom Bethany has never met. She also lives in Sanderfield, Illinois. Bethany overhears her father telling Myrlie that Bethany does not know anything about Elizabeth. She soon realizes her parents are abandoning her without an explanation, but she begrudgingly settles in.
As she lives with Myrlie, her aunt unwittingly is able to guess all of Bethany's favourite foods. Bethany's interest in Elizabeth is sparked when one of Myrlie's friends mistake Bethany for Elizabeth. Though Myrlie has promised Walter not to tell Bethany about Elizabeth, her aunt reveals that Elizabeth was Bethany's sister, who died in a car accident before Bethany was born. Hillary had been driving the car and Myrlie's husband and Elizabeth died in the crash, though Myrlie's daughter Joss survived. Joss, who had been Elizabeth's best friend, initially mistakes Bethany for Elizabeth, noting that their exact resemblance. After seeing some home videos of Elizabeth and Joss as children, Bethany confirms that she and Elizabeth are identical, save a small scar under Elizabeth's left eye.
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Elizabeth Krull - Elizabeth Krull was the daughter of Walter and Hillary. She is Bethany's older sister and died in a car accident on her 13th birthday along with her Aunt Myrlie's husband.
Det är en moster, inte mormor, och åldern är tretton, men det är föräldrar som släpper tjejen och hon lär sig att hon är en klon av sin döda syster som dog i en bilolycka.