Although you two have a difference in status, if you [Munenaga] were greedy and crooked in mind and had not understood the reason behind everything, your elder brother’s disinheritance would never have been lifted. Your elder brother, Munenaka may become a Buddha due to his fervent belief in the Lotus Sūtra. However, your father would certainly go to hell for disinheriting his own son, who is a practicer of the Lotus Sūtra. In this case you would lose your older brother and father and become like Devadatta. However, as you are born wise and without greed unlike those born in the Latter Age of Degeneration, three of the Ikegami family attained Buddhahood together, saving everyone on the father’s side as well as the mother’s side.

Hyōesakan-dono Gohenji, Answer to Lord Ikegami Munenaga, Writings of Nichiren Shōnin, Volume 6, Followers I, Page 97

As you and your elder brother were born in the Latter Age of Degeneration in an outlying country and have faith in the Lotus Sūtra, I was sure that demons would possess the nation’s ruler or your parents and persecute you. But as I expected, despite your father disowning you repeatedly, you two brothers held onto your faith. Are you the reincarnation of Princes Pure Store and Pure Eyes, who led their father King Wonderful Adornment? Or is this through the discretion of Bodhisattva Medicine King and Bodhisattva Superior Practice [sic]? Your father’s disinheritance was revoked in the end and you were able to carry through with filial piety as before. Are you not filial sons in the truest sense of the word? I am sure the various heavenly beings are pleased, and the ten female rākṣasa demons, protectors of the Lotus Sūtra, accept your aspiration. Moreover, there is something heartfelt about you. When my doctrine spreads as widely as predicted in the Lotus Sūtra, I hope to share the joy with you.

Kōshi Gosho, A Letter to Filial Sons, Writings of Nichiren Shōnin, Volume 6, Followers I, Page 103-104

The letters in the first half of Volume 6, the first of the Followers collections, were written to one or the other of the two Ikegami brothers, Munenaka and Munenaga, or their wives.

Munenaka, also called by Nichiren Emon no Tayūsakan, was a warrior who lived in the Ikegami District of Musashi Province (Tokyo today). His warrior father, Yasumitsu (Saemonnotayū), was a devoted follower of Ryōkan-bō Ninshō, whom Nichiren criticized harshly. Yasumitsu twice disowned Munenaka in an effort to persuade the brothers to abandon Nichiren. Munenaga stood to gain his brother’s inheritance if he renounced the Lotus Sūtra. But the brothers remained steadfast. Eventually, Yasumitsu was convinced to change his own faith and became a follower of Nichiren Shōnin.

This would make a wonderful plot outline for a movie or at least a novel.