SANTA ROSA (CBS SF) — Fentanyl likely played a role in the tragic deaths of a 29-year-old Santa Rosa father and his infant son, according to police and family friends.

Santa Rosa police announced Tuesday that Patrick O’Neill never regain consciousness before he passed away late Monday.

While the investigation continued into the cause of O’Neill and his young son’s death, a family friend — Michael Arevalo — told the San Francisco Chronicle that Fentanyl likely played a role in both deaths.

O’Neill was rushed to a hospital Saturday afternoon. Police said there were no signs of violence at the home, but they found evidence of possible drug use next to where the child’s body was discovered.

It all started after the toddler’s mother came to check on them at a western Santa Rosa house, police said.

When officers arrived at the house in the 200 block of Darek Drive about 12:50 p.m. Saturday, they found O’Neill and the baby lying next to each other on the floor of a back bedroom. Despite lifesaving efforts by medical personnel, the baby was pronounced dead at the scene.

In addition to the baby and the 29-year-old, police found items “consistent with narcotic use.”

Police encourage anyone with information about what happened at the Daren Drive house to call the Santa Rosa Police Department’s Violent Crimes Investigation Team at (707) 543-3590.

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