Is the husband obligated to fast or pay expiation (diyah), given that he bears 25% of the traffic accident fault, after a car accident caused by another vehicle led to the death of one of the neighbors' children whom he was driving to school?

There is no guarantee [of compensation], nor blood money (diyya), nor expiation (kaffara) due from the husband if he did not cause the accident, or violate traffic laws, or fail to avoid the accident. However, if it is proven that he bears a percentage of the fault, then he is responsible for that percentage of the blood money. In the event that two different causes contribute to the harm, responsibility falls on each party responsible according to their percentage of influence. If their influence is equal or the percentage is unknown, then the liability is equally divided between them. It is advisable to refer to the Sharia courts to examine the circumstances of the accident.