Chad Daybell’s adult children revealed what they believe to be their mother Tammy Daybell’s cause of death — while also insisting they believe their father is innocent.

As CBS News reports, Daybell’s adult children said police told them Tammy Daybell died of asphyxiation. Authorities have not yet released the result of Tammy’s autopsy, which was performed after investigators exhumed her body in December 2019. The autopsy remained pending for over a year; after it was completed, Daybell was charged with first-degree murder in his wife’s death.

“They told me that she’d been asphyxiated … but we never saw an autopsy,” Chad’s son Garth Daybell reportedly said in an interview for a “48 Hours” segment set to air Wednesday night.

“Asphyxiation doesn’t necessarily mean smothered,” added Mark Daybell. “According to my understanding, it just means the breath was interrupted. And in the end, she wasn’t able to breathe. And according to that, there’s more facts we need. We don’t just say, ‘Oh, well, bye, Chad.’ No there’s still love, there’s still connection.”

Death by asphyxiation occurs when a victim’s oxygen supply was cut off. While, in criminal cases, this is often the result of strangulation or suffocation, there are numerous ways to die by asphyxiation.

The children said it the interview that it was their decision, not their father’s, to decline an autopsy following Tammy’s sudden death at age 48. They also said their mother was in failing health, which has not previously been stated, and appears to conflict with earlier reports that Tammy had no known medical conditions.

“The narrative is that he was going, ‘No, no, no autopsy.’ But he was standing there — in complete shock, traumatized, letting us make the decision,” Chad’s daughter Emma Murray said in the interview.

“If he was trying to hide something, you — I wouldn’t leave something like that up to my kids if I was trying to hide something.”

Daybell has pleaded not guilty to multiple charges in the death of his former and wife, and his stepchildren. The 16- and 7-year-old children of Daybell’s current wife Lori Vallow were found dead in his backyard in Salem, Idaho, last summer. As previously reported, Daybell’s children say they believe he had nothing to do with the children’s murders and that he was framed.

“We presume innocence in this country. Just because things look funny, we don’t send people to jail,” Murray told 48 Hours.

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