Two people have been arrested in the suspected opioid overdose of a 4-year-old Milwaukee boy who would be the seventh child under 5 to die after swallowing opioids in Milwaukee County in the last 19 months, if further toxicology tests in the latest case confirm preliminary results, according to authorities.

Tyranne Beckless was pronounced dead at a home on Milwaukee's north side on Saturday, according to the Milwaukee County Medical Examiner's Office, which describes the death as a "probable opioid overdose."

Two people have been arrested, Milwaukee Police Sgt. Timothy Gaurke said Thursday, but he declined to provide additional details because of the ongoing investigation. Further toxicology testing was being done, the medical examiner's office said.

Toddlers are some of the youngest victims of the nation's opioid epidemic. The number of children's deaths is relatively small compared to the overall toll from opioids, but toddler fatalities have climbed steadily over the last 10 years.

In 2000, 14 children in the U.S. under age 5 died after ingesting opioids. By 2015, that number climbed to 51, according to the Centers for Disease Control and Prevention.

Three people have been charged in Milwaukee County this year with the deaths of their young children, including Martis Dickerson, 39, accused of second-degree endangering safety in the death of her 2-year-old son, James Vessell. The child died after ingesting opioids prescribed to his mother that were left in a purse on a bed where the boy was playing, according to a criminal complaint. Dickerson is scheduled to be arraigned next week. Court records do not list her attorney.

Sara J. Schreiber, who oversees the toxicology lab at the Milwaukee County Medical Examiner's Office, recently said that in most cases the opioid deaths of young children are preventable.

"In the case of a toddler, especially if they're mobile, they've got access to a lot of things in the home as long as they're within their reach," Schreiber said. "So the risk is there and the danger is there inherently just by having those drugs available in the home."

Margarita Balderas, 34, and Darrell Woodson, 35, were charged in February with party to second-degree reckless homicide in the 2016 death of their daughter, London Maria Woodson. She was pronounced dead at Children's Hospital in Milwaukee Aug. 15, just a day before her third birthday.

The girl's death was attributed to an acute toxic mix of oxycodone and trazodone, according to the Milwaukee County Medical Examiner's Office autopsy report. An older sibling told child advocates that Woodson and her mother would break off pieces of prescription pills and give them to London in order to get her to sleep, according to the criminal complaint.

Balderas' attorney, Thomas Harris, said the case is still in the early stages and that Balderas remains incarcerated. Woodson's attorney did not immediately return a call for comment on the case.