Authorities say Caffey's teenage daughter, Erin, and the 20-year-old Wilkinson spent weeks planning to kill the girl's family because they were forbidden to date.
The parents were shot while they slept, and the house was torched. Only Caffey's father survived, crawling out of his burning home after being shot five times.
Erin Caffey and 19-year-old Bobbi Johnson, who also pleaded guilty, have also received lengthy prison sentences.
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