New details point to a possible premeditated plot in the family murders at Great Wolf Lodge in Pennsylvania, a private investigator says.

Metallica Rose Harrison, 27, is facing two counts of criminal homicide after prosecutors say she stabbed and killed her husband, Charles "Chaz," and the couple's 3-year-old son, Tristan. It happened at the resort in the Poconos region of Pennsylvania.

According to a criminal complaint, knives recovered by investigators on scene did not match knives belonging to the resort.

The document says, "Both knives had teal green handles, which Great Wolf staff confirmed was not a type kept by the lodge."

The family has confirmed that autopsies for both victims were being conducted. Investigators discovered the father and young son slaughtered in a hotel room at the resort on Monday.

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📸 Instagram: possible murder weapons brought from home on the lengthy vacation suggest possible premeditation in the horrific case.

"From the cursory file that we can look at, we being the general public, it looks like there are certain elements that are already met," he said.

Various news outlets also report that Harrison never wanted to be pregnant in the first place and was allegedly resentful toward her own son.

Why? Reports say she wanted more alone time with her husband.

Family also allegedly told investigators that the mother accused of the killings "was dominant, controlling and isolated the three of them from her husband's family for the last three years," WNEP reported.

While the investigation into the killings continues, Chaz's family members grapple with their new normal.

"His love for his wife and child was out of this world and, sadly, is the reason why he lost his life and his son's life," Chaz's sister shared in an update on a GoFundMe page.

"I’m not here to say anything bad about his wife. I know my brother would not want me to do that," she went on to say.

She is sitting in a Monroe County jail cell and due in court on Oct. 21.