A couple is behind bars after being accused of trying to sell a 5-month-old baby for $3,000 on Craigslist, according to the Greene County Sheriff's Office. John David Cain and Deanna Lynn Greer have been charged with aggravated child abuse and aggravated child neglect. Authorities say the couple met an undercover agent at the Dollar General parking lot. He paid them in cash and was given the baby. The infant is in custody of the State Department of Children's Services.