Rabbi Yosef Wald, rabbi and educator at the Jerusalem Yeshiva Letz'irim and researcher at the Halacha Berura Institute, passed away during the holiday.
His son is Yehuda Wald, a member of the Central Bureau of Labor and head of the National Union party.
A year ago, the family lost their son, Ariel Zeev Wald.
The National Union party issued a statement at the holiday's close expressing deep sorrow over Rabbi Wald's passing.
"During Simchat Torah, Rabbi Yosef was called to the Yeshiva above after a long period of torment and suffering from a serious illness. Rabbi Wald's great difficulty and pain were increased by the loss of his son and the loss of students in the serious terrorist attack on Yeshiva Letz'irim," referring to the Merkaz Harav yeshiva massacre in which six of the victims were students from the Yeshiva Letz'irim (for the young), the adjoining yeshiva high school.