Does a father incur sin for refusing an autopsy for his deceased son to determine the cause of death, and what should he do if sin is incurred?

The deceased's body is to be respected, and it is impermissible to dissect it or exhume its grave except for a definite or preponderant benefit, or to avert a confirmed necessity. The Prophet, peace and blessings be upon him, said: "Do not sit on graves," and "Breaking the bone of a dead person is like breaking it when he was alive." The father's refusal to dissect the child's body is correct, as there is no definite benefit or necessity that calls for it, and the default is the innocence of the mother and brother. Medical possibilities for the cause of death at this age do not necessitate dissection. You should be patient and say: "Indeed we belong to Allah, and indeed to Him we will return."