[W]hat karma made you put faith in the Lotus Sūtra? As your late son had faith in the Lotus Sūtra, is it at his urging that you became a follower of the Lotus Sūtra? Due to the great merit of having faith in this sūtra, I have no doubt that you will meet your son upon visiting the Pure Land of Mt. Sacred Eagle.
In the past a calligrapher named Wu-lung in China fell into hell for slandering the Lotus Sūtra, but he became a Buddha when his son Yi-lung copied the sūtra, offering its merits to his late father. Also, King Wonderful Adornment was an evil ruler, but was led by his two sons, Pure Store and Pure Eyes, in practicing the Lotus Sūtra becoming the Śāla Tree King Buddha. These are some examples in which parents attained the status of Buddhas through their children’s faith in the Lotus Sūtra.
This is especially true with a mother and her children. The reason why it is so is that children’s flesh is mother’s flesh. A mother’s bones are the same as her child’s bones. It is said that when a pine tree grows thick, an oak tree is delighted. When a turf grass dies, an orchid cries. Even among plants, which do not possess minds, joy and sorrow are shared between them. How much more so between a mother and her child! A mother gives birth to her child after nurturing the baby in her womb for nine months and raises her child for years after that. It is only natural for a mother to hope that at death her own children will carry her coffin and bury her. How does a mother feel if her children precede her in death? What can she do with the shame of seeing her child’s funeral and the anxiety about her future life?
Buddhist sūtras cite such tales as a mother pheasant which refused to escape a brush fire and kept on sitting on her eggs till she was burnt to death and a poor woman who refused to take her hands off her baby while swept away by a swift current of the Ganges River. The pheasant then is Bodhisattva Maitreya today, while the woman who was drowned in the Ganges was reborn as the King of the Mahābrahman Heaven, not to speak of yourself who has become Kōnichi Shōnin (Rev. Kōnichi), a practicer of the Lotus Sūtra, due to your deep love for your son. I am sure that you and your son together will visit the Pure Land of Mt. Sacred Eagle. How happy for you two to see each other there! How delightful for you both!
Kōnichi Shōnin Gohenji, A Reply to Rev. Kōnichi, Writings of Nichiren Shōnin, Followers II, Volume 7, Page 155-156