By Helen Pow An 84-year-old man has allegedly shot dead his chronically ill wife and daughter-in-law before turning the gun on himself in a tragic 'mercy killing.' Dan Crabtree, 80-year-old Carol Crabtree and 62-year-old Rita Delehanty were found dead in the elderly couple's home in Hacienda Heights, California, on Wednesday morning. Jim Crabtree, 55, the couple's son and Delehanty's husband of 25 years, said all three suffered from chronic illnesses, which is what led to the apparent murder-suicide. 'This is the classic ending of three people with terminal illnesses,' he said. SCROLL DOWN FOR VIDEO Dead: Dan Crabtree, 84, pictured, allegedly shot dead his elderly wife Carol, right, and daughter-in-law before turning the gun on himself in a tragic 'mercy killing'
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Dan Crabtree, 84, Carol Crabtree, 80, and Rita Delehanty, 62, were found dead of gunshot wounds in the elderly couple's Hacienda Heights home on Wednesday morning
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Jim Crabtree, 55, the couple's son and Delehanty's husband, said all three suffered chronic illnesses, which led to the apparent murder-suicide
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Delehanty was in the mid-stages of Alzheimer's and Jim Crabtree dropped her at his parents house most mornings so he could go to work
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Son said he was sad but somewhat relieved after the death of his wife who no longer knew who he was or that they were married
He explained that his wife suffered from mid-stage @placeholder, his father from early-stage Alzheimer's and his mother from debilitating chronic joint pain that forced her to use a wheelchair.