Kristina Bumphrey/WENN 1 / 12
Kristina Bumphrey/WENN 1 / 12

Usher is fighting back against claims that he's a bad boss. TMZ says a former nanny has filed a lawsuit against the crooner alleging she was mistreated while working as a part-time caregiver for his two sons.

Cecilia Duncan contends that she was "overworked without being paid overtime," but her concerns were ignored by Usher for more than a year. She was fired in September 2012, nearly two years after being hired. She was apparently not given her ostensibly overdue overtime pay.

According to TMZ, she's seeking a six-figure payout for wrongful termination, failure to pay wages and other purported wrongdoing.

But Usher's camp insists this is a "frivolous lawsuit" and Duncan's accusations are "completely false."

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