A Unionville woman was sentenced to 10 years in state prison Thursday for her part in a plan to set fire to her father-in-law?s house in hopes of killing him.

Tracey Doyle pleaded guilty to arson in the third degree after admitting to setting five separate fires last October at John Doyle?s Unionville home. Investigators said the 35-year-old mother's goal was ultimately to kill her father-in-law.

Doyle?s two teenage children will also be doing time for their parts in the crime. Nineteen-year-old Shannon Kays was sentenced to 2-6 years in prison. Her 16-year-old brother, Donald Doyle, was sentenced as an adjudicated youthful offender to 1-3 years in jail.

The intended victim, 71-year-old John Doyle, still doesn?t believe his family actually meant to harm him. The family members faced attempted murder charges in addition to the arson. Those charges were reduced when they took their plea deals. A fourth person involved in the plot, 22-year-old Michael Spring, of New Jersey, is scheduled to be sentenced at a later date.