One soul two lives

There is a saying in Japanese
三つ子の魂百まで　Mitsugo no Tamashii Hyaku made
It is believed that it takes 3 years for a soul to fully form and solidify which would last for a lifetime.
Just as the Nanase twins reached the tender age of 3 a life-threatening fever nearly took the life of the younger twin. Just when all hope had been lost he miraculously recovered.
Meanwhile, tragedy struck a family of three who had been awaiting the arrival of their newest family member. All of the family members perished in the tragic car accident with the exception of one child who escaped with his bare life. However, witnessing the death of his parents and possibly younger brother traumatized the young child to the point he became completely despondent. From that point he had become a completely living doll.