Shonan Soke (湘南宗化)
His childhood name was Hiroi.
He was found in front of a monument for the soul of Yone (another story tells it was in front of the house of the Yamauchi family) and brought up like a true son by Katsutoyo and Chiyo (Kenshoin), who were depressed for having lost their only daughter Yone (6 years old) in the earthquake in 1586 in Nagahama, Omi Province. There is still another story that he was in fact an illegitimate child of Katsutoyo.
However, around 1595, when Hidetsugu TOYOTOMI committed seppuku due to the succession dispute, he left home and became a priest under the order of his father-in-law, Katsutoyo. Katsutoyo may have thought it would cause a problem in the Yamauchi family if Hiroi, who was out of the bloodline of Yamauchi, took over the family.
Hiroi practiced asceticism in Kyoto to become Soke SHONAN Osho, and at the same time became a chief priest of Gyuko-ji Temple in Tosa Province given by his parents-in-law. Soke SHONAN was the second chief priest of Myoshin-ji Temple Daitsu-in in Kyoto, and became such a high priest as to receive an imperial sanction for a purple canonical robe from the Imperial Court. One of his disciples in Myoshin-ji Temple (who also accompanied him to Gyuko-ji Temple in Tosa) was Ansai YAMAZAKI, who later returned to secular life. Myoshin-ji Temple Daitsu-in later became the family temple of the Yamauchi, and the Kyoto graveyard of Kazutoyo and Kenshoin is also located there.
After the Yamauchi family entered Tosa Province, Soke SHONAN concurrently served as the chief priest of Gyuko-ji Temple in Tosa and the chief priest of Myoshin-ji Temple Daitsu-in, and restored Enmei-ji Temple on Mt. Kotoku in Tosa Province (burnt in the Edo period).
By the way, Katsutoyo adopted Tadayoshi YAMAUCHI, the son of his younger brother Yasutoyo YAMAUCHI, as the successor of the Yamauchi family. When Kazutoyo died in the fall of 1605, Kenshoin made Yasutoyo the guardian of Tadayoshi, left Tosa in six months, resided near Myoshin-ji Temple where Hiroi lived, and spent the rest of her life in Kyoto. To Kenshoin, Hiroi was the reincarnation of Yone.