What is the ruling regarding a brother who murdered his three siblings due to a dispute over land, where one of them intended to plant cannabis, and are the murdered considered martyrs and will they be saved from the torment of the grave if they were about to plant something forbidden?

Every Muslim who is unjustly killed receives the reward of martyrdom in the Hereafter. However, in this case, the injustice is not unalloyed, due to the combination of two descriptions: first, they were unjustly killed, and second, their desire for and pursuit of what is forbidden.

The worldly judgment regarding them rests with the Sharia court. As for the Hereafter, their matter is with Allah. It is hoped that Allah will expiate their intention due to the undeserved killing they suffered. What is prescribed is to supplicate for them with goodness and forgiveness.

It is not permissible to say, "the destinies willed"; because the will belongs to Allah alone.