Because the fire was set deliberately they won't cover the cost. It as not accidental and as the son did not insure him self, the insurance company will not pay out and I believe they won't because it wasn't a tenant, therefore, they wouldn't cover any lost of property or life. But if the son had his own personal insurance to cover himself for any injury,loss of property, they they would have paid out. I thinks its because he lives in the same house and a relative, and the fire was arson,they will not pay, then again it depends on the insurance policy.