WREG-TV, Memphis, reported she is still in police custody.
Harless is accused of forging 121 checks totaling more than $64,000 since 2011 when she stopped working for the family of Timberlake, a 32-year-old pop star and actor.
Sheriff deputies said Harless wrote herself checks, forging her brother Paul Harless' and sister-in-law Lynn's names, then cashed them and kept the money.
Lynn married Paul when Timberlake was 5.
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