Complex sentence: Naftali Yehuda Horowitz-The Bostoner Rebbe, is an American chassidic rabbi, son of the late Grand Rabbi Levi Yitzchak Horowitz, the Bostoner Rebbe, a scion of the Boston Hasidic dynasty.
Split into simpler sentences: Naftali Yehuda Horowitz, the "Bostoner Rebbe", is an American chassidic rabbi. Horowitz is the son of Levi Yitzchak Horowitz, the previous Bostoner Rebbe, and a scion of the Boston Hasidic dynasty.