A 23-year-old mother has been charged with second-degree murder over her child's fentanyl-related death that happened last year.

After a yearlong investigation, police charged a woman with second-degree murder after her child swallowed a fatal dose of fentanyl while they were living in Mooresville. Even a pencil tip amount of the synthetic opioid pain reliever drug can be fatal, according to the U.S. Drug Enforcement Administration.

A mother in Iredell County is charged with murder after her child, who was less than two years old, died from fentanyl toxicity. According to the Mooresville Police Department, officers were called to a home on Ridge Avenue in Mooresville on Feb.