Monroe man arrested for murder of girlfriend’s 2-year-old daughter in Snohomish County

A 27-year-old Monroe man is under arrest, charged with murdering his girlfriend’s 2-year-old daughter and assaulting her 5-year-old son in Snohomish County.

The Pacific Northwest Violent Offender Task Force arrested the suspect Tuesday night at a motel on Old Owen Road. He faces charges of second-degree murder of a child and second-degree assault of a child.

Girl died at Seattle Children’s Hospital

“On December 1, 2025, Sheriff’s Office deputies responded to a residence in the 300 block of Avenue J in Snohomish for reports of a 2-year-old child who was unresponsive,” the Snohomish County Sheriff’s Office stated in a news release Wednesday. “Fire personnel performed CPR on scene, and the child was transported by aid to Providence Regional Medical Center.”

The girl was then transported to Seattle Children’s Hospital, where she died on December 7, 2025.

Injuries ‘inconsistent with a fall’

Detectives said the children were at home in the sole care of the suspect at the time of the incident.

“The suspect stated the 2-year-old victim fell in the bathroom and sustained a head injury; however, the victim’s injuries were inconsistent with a fall,” the release said.

The Snohomish County Medical Examiner’s Office ruled the 2-year-old’s death a homicide, determining the cause of death was blunt force head trauma.

Detectives believe the suspect also caused neck and arm injuries to the 5-year-old boy.

The suspect is due in court Wednesday afternoon.

Frank Lenzi is the News Director for KIRO Newsradio. Read more of his stories here.

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