Yaakov Schneerson
Reb Yaakov Schneersohn (after 5582/1822 – 5597/1837) was the sixth son of the Tzemach Tzedek.
He was born between Rabbi Yosef Yitzchak Schneersohn of Avrutch and the Rebbe Maharash. He was named after the teacher R' Yaakov Minavitch, the father of Rebbetzin Shaina, wife of the Mitteler Rebbe.
He married on Shabbat Parshat Behaalotcha, in the month of Sivan 5595/1835, Maras Freida, daughter of R' Baruch Klutzker (grandson of the Alter Rebbe), son of Rebbetzin Freida, daughter of the Alter Rebbe who was then living in Orsha (and after his wedding, he lived near his father-in-law and therefore was called "Yaakov of Orsha").
Afterwards, he traveled to Tulchin, where he became very ill. When Rebbetzin Chaya Mushka (wife of the Tzemach Tzedek) came to her husband, she said to him: "You pray for the entire world, only for your son you did not pray." He answered her, "Hashem concealed it from me and did not tell me, and a prisoner cannot free himself from prison."
R' Yaakov passed away in the city of Tulchin in the year 5597/1837 (apparently). He left behind his son, R' Shneur Schneersohn (grandson of the Admor the Tzemach Tzedek).