The Soka Gakkai Dictionary of Buddhism
Jakunichi-bo Nikke[寂日房日家] (n.d.)
(1) A disciple of Nichiren, also known as Jakunichi-bo. He was a younger brother of Sakuma Hyogo-no-suke Shigesada, a follower of Nichiren who lived in Okitsu in Isumi District in Kazusa Province, Japan. In 1265 he became a follower of Nichiren. Nichiren addressed his Letter to Jakunichi-bo to him in 1279.
(2)［寂日房日華］(1252-1334): A disciple of Nichiren, also known as Nikke. According to one account, he was the son of Akiyama Nobu-tsuna, the lord of Kajikazawa in Kai Province, Japan. He entered the priesthood under Nikko, and in 1276 went to Mount Minobu to serve Nichiren. After Nichiren's death, he was assigned to the twelfth-month shift in the rotation system for attending to Nichiren's tomb. In 1289, when Nikkoleft Minobu to establish what later became Taiseki-ji temple at the foot of Mount Fuji, Nikke accompanied him. He was one of Nikko's six elder disciples.