Is it obligatory to fast for two consecutive months as an expiation for the death of the elder brother in a car accident resulting from driving at excessive speed?

If it is determined that the questioner was the cause of his brother's death, then he owes blood money (Diyyah), which his 'Aqilah (male relatives on the father's side) must pay to his brother's heirs, and he is entitled to none of it. He is also obligated to perform expiation (Kaffarah), which is the freeing of a believing slave. If he cannot find one, then he must fast for two consecutive months, based on the statement of Allah Almighty: "It is not for a believer to kill a believer except by mistake. And whoever kills a believer by mistake - then the freeing of 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 the freeing of 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 the freeing of a believing slave. And whoever does not find [one] - then a fast for two consecutive months as repentance to Allah. And ever is Allah Knowing and Wise."