Officials at the Los Angeles County Department of Children and Family Services were told the reality TV teenagers - the daughters of Kim Kardashian's mother Kris and former Olympic athlete Bruce Jenner - were in danger in the family household.
Social workers and police investigated the caller's allegations of possible abuse, but decided there was no merit to the accusations - and now the family is taking action to find out who made the claim.
A representative for the stars tells U.S. website TMZ.com, ""It's such a shame that anyone can make up such hurtful and hideous untruths especially when children are involved.
""We are taking this matter very seriously and investigating to find out who is responsible for fabricating such a terrible story and will take the necessary legal action so that this does not happen again.""
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