Complex sentence: The oldest was Mariam she married Reb Nusen Baumhaft who was the Rosh Yeshiva of Klausenberg, both Mariam and her husband together with fourteen of their children perished in the Holocaust.
Split into simpler sentences: The oldest was Mariam who married Reb Nusen Baumhaft who was the Rosh Yeshiva of Klausenberg. Both Mariam and her husband together with fourteen of their children perished in the Holocaust.