Police responded to a home on Weequahic Avenue around 8 a.m. where they found Aydin Brown unresponsive. He was rushed to the hospital where he was pronounced dead.
Authorities announced Monday they were searching for the mother’s boyfriend for questioning.
Mark Harper, 36, of Union, was later arrested by Essex County Prosecutor’s detectives and charged with endangering the welfare of a child.
He has been identified as the boyfriend of the child’s mother and was believed to be caring for the child at the time of his death.
The Medical Examiner’s Officer will determine the cause of death. The incident remains under investigation.
Devastated family members described the Aydin as a healthy, happy and loving young boy.
Harper is in the Essex County Correctional Facility pending a detention hearing in NJ Superior Court.
Anyone with information is asked to call the department’s 24-hour Crime Stopper tip line at 1-877-NWK-TIPS (1-877-695-8477) or 1-877-NWK-GUNS (1-877-695-4867).