Murder weapons in Great Wolf Lodge family massacre may offer premeditation evidence: private investigator

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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Harrison's stepmother told Fox News Digital it's possible that the suspect may have drained the family's 401(k) account ahead of the three-week stay at the resort.

The family of three lived in a modest home in Towanda, Pennsylvania. Their home is around 100 miles northwest of the resort.

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"Theres so many lodges up in the mountains between where they lived and where they went to, that Id be curious as to why they picked that lodge," said private investigator Rod Devine.

His firm is based in the Lehigh Valley area of Pennsylvania, south of the Poconos.

"Theres a lot of moving parts here that the investigators will be looking at," he said.

In his experience, he has sat face-to-face with convicted killers and homicide suspects.

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He explained that the allegations of the drained retirement fund, the nature in which both the husband and toddler were killed, and the possible murder weapons brought from home on the lengthy vacation suggest possible premeditation in the horrific case.

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"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.

Harrison's stepmother previously told Fox News Digital the killings appeared to be "p