Detectives don't know for certain what led a father to kill his wife and two teenage children before burning down their $1.6million  mansion and committing suicide last May, but they did find evidence of mounting tension in the weeks leading up to the tragic incident. The bodies of the four members of the Campbell family were discovered six months ago in the Avila, Florida home they were renting from retired tennis professional James Blake. Investigators determined that Darrin Campbell was the family member to carry out the horrifying murders of his wife Kimberly, 51, and their children Collin, 18, and Megan, 16, before setting fire to the house and killing himself.
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Darrin Campbell shot dead his wife and their teenage son and daughter last May before setting their house on fire and turning the gun on himself
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The family was renting a $1.6million mansion in Avila, Florida from former tennis star James Blake
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Sheriff's detectives wrapped their investigation and published a report Wednesday finding 'no motive' for the murders and suicide
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However, the report noted that the family was dealing with financial issues
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Wife Kimberly  told friends the week before that she and her husband 'don't talk much anymore'
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Daughter Megan, 16, started showing fresh bruises in the weeks leading up to the murders but blamed them on dance injuries
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Campbell was also allegedly concerned over his 18-year-old son Collin's college baseball prospects
Also, bills that were paid by @placeholder began being partially paid by Darrin or not paid at all.'