Today, on the 23rd of Av, is the Yahrtzeit of Rabbi Yaakov Yisrael Kanievsky, the Steipler Gaon (1899-1985).
Brother in Law of the Chazon Ish & father of Rav Chaim Kanievsky Zt”l. Though he held no official position, he was a Gadol & Posek of his time.
Mechaber of the Kehilas Yaakov, Birkas Peretz, Orchos Rabeinu etc.