(CNN) -- A Florida mother has been arrested for her alleged part in attempting to sell her 8-week-old son, police said Tuesday. Stephanie Bigbee Fleming, 22, is the third person charged in the case. Her mother, Patty Bigbee, 45, and her mother's boyfriend, Lawrence Works, 42, were arrested and charged last week. Fleming was already incarcerated on unrelated charges. Bigbee is accused of having approached a potential buyer in late October, offering to sell the infant for $75,000, the Florida Department of Law Enforcement (FDLE) said in a statement. The would-be buyer then contacted authorities. Together, they negotiated the price of the baby down to $30,000 and agreed to meet, the statement said. Bigbee and her boyfriend arranged the sale for last Friday, at which point officers swept in.
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Stephanie Bigbee Fleming, 22, was already incarcerated on unrelated charges
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She conspired with her mother to sell the infant, police say
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The baby remains in the custody of the Florida Department of Children and Families
Fleming's bond was set at $50,000, while @placeholder's was put at $100,000.