A New Jersey mother has been charged with aggravated manslaughter weeks after her 2-year-old son ingested fentanyl and died, authorities said. Natalie M. Sabie, 34, of Lacey, was also charged with three counts of endangering the welfare of a child and possession of fentanyl following her arrest Friday, the Ocean County Prosecutor’s Office announced Tuesday. Police found the toddler unresponsive when they arrived at Sabie’s home Sept. 7, officials said. Emergency workers treated the boy and brought him to an area hospital where he was pronounced dead. Toxicology results released on Oct. 12 reve…