CHICAGO (CBS) — A 34-year-old Chicago man has been charged with killing his girlfriend’s 4-year-old son and the boy’s mother has been charged with child endangerment and concealing a homicide in her son’s death.

Cesar Ruiz, of the 5100 block of South Trumbull Avenue, has been charged with first-degree murder and concealing a homicide in the death of Christopher Valdez on Friday, police said.

His girlfriend, Crystal Valdez, 28, also of the 5100 block of South Trumbull Avenue, was charged with endangering the life of a child and concealing a homicide, police said.

christophervaldez Mother, Boyfriend Charged In Death Of 4 Year Old Boy

Christopher Valdez (courtesy family/Dawn Valenti)

Christopher died on his fourth birthday on Friday afternoon in what police described as a “possible domestic situation,” at Christopher’s home in the 5100 block of South Trumbull Avenue.

An autopsy on Saturday determined he died from multiple blunt force injuries and child abuse, according to the Cook County medical examiner’s office. His death was ruled a homicide.

Police have yet to reveal details of Christopher’s death, other than to say he was dead when police officers arrived at the boy’s home on Friday.

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