How much flesh would a Woodchipper chip, if a Woodchipper could chip flesh?

Overview

Jon, Tom, and Denise accidently kill their senile old Aunt while she's looking after them while their father is away on business. Not sure what to do, they decide to dispose of the body in the rented woodchipper in the backyard. But more trouble comes a-knocking when their cousin Kim, their Aunt's son, shows up unexpectedly.