R. took his mother on a motorcycle

R. took his mother on a motorcycle

R. took his mother on a motorcycle to visit relatives.
On the way, the bike skidded and it overturned. R. remained safe and sound, and his mother died. On this basis, a conflict arose between R. and his sisters. The sisters, accusing R. of the death of the mother, refused to give R. his share in the inheritance. R. insisted on giving him a share, claiming the accident was due to the condition of the road, and the criminal case against him was terminated.
Does R. have the right to inherit?

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