Decree
Shana Decree (L), Dominique Decree. Bucks County, Pa., District Attorney's Office

Earlier this week Pennsylvania woman and her teen daughter were arrested after allegedly killing five relatives, including three children, inside an apartment. Now relatives of both the victims and the alleged killers are saying they tried in vain to prevent this from happening.

According to Philadelphia ABC affiliate WPVI, family members believe a religious cult may have led Shana Decree and her 19-year-old daughter, Dominique to allegedly commit the gruesome murders in Bucks County.

READ MORE: Pennsylvania Mother, daughter charged with gruesome murder of five relatives in one house

Monday, responding officers discovered the bodies of Shana Decree’s own children, Naa’Irah Smith, 25, and Damon Decree Jr., 13, Shana’s sister, Jamilla Campbell, 42, and Campbell’s 9-year-old twin daughters, Imani and Erika Allen.

Court documents report the mother and daughter duo told authorities that everyone in their Morrisville house had been fixated on suicide leading up to the killings.

“They were all going through something religiously and they decided to drag the kids into it,” said Destiny Harris, the half-sister of the slain twins.

Damon Decree, Sr., whose ex-wife and daughter are accused, confirmed the family had been “talking about demons being all around them,” before the two allegedly killed his son.

READ MORE: Teen who stabbed classmate to death at school charged with murder

“Apparently they had dissected into some type of cult that they materialized online. I don’t know how or what kind of cult,” explained the grieving father.

Decree said the bizarre behavior had been going on for a month and that children services had been called to check on the home. Saturday, the Bucks County Children and Youth Social Services Agency showed up to an apartment complex to perform a welfare check, but no one answered the door.

Monday when the social worker returned and contacted a maintenance worker to let her in, police were contacted to investigate.

Harris believes the twin girls — who would have been 10 years old on Friday — should have been protected from whatever the other relatives in the homes were practicing.

READ MORE: Ohio woman accused of kidnapping her children arrested after allegedly killing their father

“They were 9. They didn’t deserve that, they didn’t need to go through that,” she said. “They should’ve never been dragged into the family issues or religion. They’re too young, they’re too young to understand. They had no choice.”

Morrisville Police Chief George McClay echoed the sentiment stating, “Two 9-year-olds can’t make that decision, and a 13-year old. Is that something in the adults’ minds? I don’t know, but it’s surely not in the 9-year-olds’ minds,” he said.

While police have yet to release an official motive for the murders, Damon Decree wants his wife and daughter held accountable for their actions even if religion was a factor.

“I don’t want them in no insane asylum. I want to see them in jail for the rest of their lives,” he said.