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I remember reading a book about a teenage girl's father marrying a woman with a son and daughter. The teenage girl soon finds out that something was weird about this new family. And what's fishy is that the woman and her children never age. They were immortal. The son and daughter try to kill the girl in a secret lake during the book sometime. And the book ends with her living with the daughter as she ages and dies like a normal human. Thank you

marked as duplicate by Rand al'Thor Oct 26 '18 at 12:32

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    When did you read the book? What language was it in, was it a translation? – Mr Lister Jun 28 '15 at 14:18
  • Closed as duplicate: there's a comment from the OP on the answer below, which has unfortunately been flag-deleted and can't be mod-undeleted. – Rand al'Thor Oct 26 '18 at 12:32

Locked in Time by Lois Duncan.

Seventeen-year-old Nore Robbins is less than thrilled when her father, Chuck, remarries. After all, her mother hasn't even been gone for a year yet, and there's something odd and sinister about his new wife, Lisette. Besides the fact that Lisette Berge is much too young to have teenage children, Nore's stepsister, Josie, has a habit of making strange comments about her family being "stuck where they are" and time "not counting for anything."Josie also has a precocious manner, flirts with boys, and wears too much makeup. She hesitates to pry into the matter. When Nore discovers Lisette's old diaries in the shed—some dating back to the 19th century—she realizes that she and her father are in terrible danger. The question is, can they leave Shadow Grove without meeting the very fate the Berges have worked so hard to bring on them?

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