"You know very well that I am an ‘ish sod,’ who keeps his mouth sealed, but there is one person who knows all of my intentions and profound secrets, and that is my eldest son,” the previous Nadvorna Rebbe of Bnei Brak, Rav Yaakov Yissachar Ber Rosenbaum ztz”l, told his closest chassidim shortly before his passing four years ago.