Is atonement required of one who caused his son to fall and die from an unguarded roof?

If the child fell from the roof and died without your knowledge of him having climbed, then there is nothing upon you. However, if you were the cause of him climbing, or you knew about it but did not protect him until he fell, then you are liable for blood money (Diyyah), which is to be paid by your 'Aqilah (male relatives on the father's side), and you are liable for expiation (Kaffarah) by freeing a believing slave. If you cannot find one, then by fasting for two consecutive months, based on the saying of Allah the Almighty: "And it is not for a believer to kill a believer except by mistake. And whoever kills a believer by mistake – then freeing a believing slave and a compensation (Diyyah) presented to his family, unless they remit it as charity. But if he was from a people hostile to you and he was a believer – then freeing a believing slave. And if he was from a people with whom you have a treaty – then a compensation (Diyyah) presented to his family and freeing a believing slave. And whoever does not find [one] – then a fast for two consecutive months as repentance to Allah. And Allah is ever Knowing and Wise." You must also be patient and seek reward from Allah, and get rid of the television, which may be a cause of such accidents.