Teen, 18, And Boyfriend, 37, Charged In 'Abusive Head Trauma' Death of Her Toddler Brother

An Iowa woman is charged in the death of her 2-year-old brother after the boy suffered head trauma authorities said was “not accidental,” PEOPLE confirms.

Denver Emery, 18, is charged with endangerment resulting in death after brother Calvin Trullinger died on May 24, according to a criminal complaint obtained by PEOPLE.

Emery’s boyfriend, 37-year-old Nicholas Rivera, has also been charged with child endangerment resulting in death, PEOPLE confirms. He turned himself in to police.

On May 24, Emery and Rivera drove the boy to Mercy Hospital in Des Moines, where doctors found he’d suffered a brain bleed and had bruising on his back. According to the police report, an autopsy showed that Calvin’s injuries were consistent with “abusive head trauma.”

According to the Des Moines Register, police Sergeant Paul Parizek said investigators are unsure if “one or both suspects were responsible for the child’s death.”

The newspaper reports that Rivera and Emery took care of the toddler for two weeks leading up to his death. During that time, police say, Calvin’s mother would check in via telephone and text messages.

According to a search warrant in the case, the toddler fell out of his crib a few days before he died. A home security video taken on May 20th — four days before the death — showed Calvin climbing over the railing of his crib before slipping and falling to the floor.

Authorities have not publicly addressed whether the fall was a contributing factor to Calvin’s death. A Des Moines police spokesperson tells PEOPLE that the investigation is still ongoing.

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Denver Emery was 17 years old at the time of the death. She has since turned 18. PEOPLE confirms that she was booked in to the Polk County jail with no bond. Rivera is being held on $50,000 bond. Neither have entered a plea, and court records do not reflect an attorney for either defendant.

Calvin’s father, Matthew Trullinger, told Local 5 TV he wants answers. He recalled visiting Calvin in the hospital before he died.

“His eyelids were half open and I could see his eyes,” Trullinger tells the station. “He was just so helpless. Doctors had machines attached to his skull. I never thought any of this would happen.”

“I just hope I wake up from this nightmare,” he said. “I just want to know what happened. I just want to know everything. I have a lot of questions and I just want to know the answers. That’s all I want.”

The family has set up a GoFundMe page to help with funeral expenses.