A 6-year-old girl called 911 to report that "her mother is dead on the bed and her father is dead in the backyard," according to a search warrant affidavit obtained by PEOPLE

By Christine Pelisek
October 06, 2016 10:34 AM

Police officers in Fullerton, California, came upon a grisly triple homicide last month, after a 6-year-old girl called 911 to report that “her mother is dead on the bed and her father is dead in the backyard,” according to a new search warrant affidavit obtained by PEOPLE.

“Upon their [the officers’] arrival, two female children, ages 6 and 9 years of age, were standing on the front porch of the residence,” the warrant affidavit states.

Inside, police say, they found the bodies of Jennifer Goodwill-Yost, 39, her 34-year-old husband, Christopher Yost, and their friend Arthur William Boucher, 28 — all dead from shotgun blasts to the head. The children were unharmed.

The Yosts were found where their children had described, Jennifer on a bed and Christopher outside, while Boucher was found on the living room couch. The warrant affidavit was filed on Oct. 3, nine days after the slayings at the Yosts’ home in the 400 block of South Gilbert Street.

Crime scene investigators collected shotgun projectile fragments from within the couch and back porch and a shotgun pellet from the back porch, according to the police documents. Blood was also found on the back of a dog and on the door of a Dodge van.

“It was a grisly crime scene, and just to imagine two children to have to wake up expecting to see mom or dad and start their Saturday morning like most kids do, to see what they saw would be difficult for anyone in law enforcement – let alone two children,” Fullerton police Sgt. Radus previously told PEOPLE.

Credit: Facebook

Joshua Charles Acosta, 21, and Frank Sato Felix, 25, have been charged with three felony counts of special circumstances murder for the shotgun shooting deaths. Acosta, the alleged triggerman, was also charged with sentencing enhancements for the personal discharge of a firearm.

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Shortly after the Yosts’ bodies were discovered, detectives learned that their 17-year-old daughter, Katlynn, was missing from the family home. She was later located in Los Angeles County, California.

The Orange County District Attorney’s Office did not comment on possible charges against a 17-year-old girl who was also detained after the killings. Police have not disclosed whether the 17-year-old was the Yosts’ daughter.

Police have said the violence was not random, and family friends told PEOPLE that Acosta and Felix were friends with Katlynn and were all involved in the “furry” community, whose members enjoy anthropomorphic animals and may dress up as the colorful characters.

Jennifer and Katlynn both attended furry events, friends said.

“I met her at a meet about a year ago or so, but she always brought a smile to everyone she talked to,” friend Kristopher Reyes told PEOPLE of Jennifer. “She was such a sweet woman and always there to help. She was always so kind to everyone and would talk to everyone. She was almost like a second mother to me.”

Credit: Fullerton Police Department

Reyes says both Felix, who went by the furname “Entey,” and Acosta had been in charge of a “furmeet” held at a park near Los Angeles.

But a family friend, who asked not to be identified, told PEOPLE that Felix had recently been banned from the Yost household.

“I remember Jen telling me a couple of weeks ago that she told Katlynn that she wasn’t allowed to hang out with him [Felix], and she also told him he wasn’t allowed to hang around Katlynn because he was a unhealthy person,” the friend said.

The Yosts had “concerns” and were looking out for Katlynn, the friend said – “it has nothing to do with being a furry.”

“If it did have something to do with being a furry, I think they would have forbidden their daughter from that lifestyle,” the friend says. “It had to do with having good social boundaries and being able to choose your friends wisely.”

Felix and Acosta are scheduled to appear in court on Oct. 28, where they will enter a plea to their charges. Neither of their attorneys immediately returned calls.