Complex sentence: Jabotinsky's older brother (Myron) died in childhood and his sister, Tereza (Tamara Yevgenyevna) Zhabotinskaya-Kopp, founded a private, female secondary school in Odessa.
Split into simpler sentences: Jabotinsky's older brother (Myron) died in childhood. His sister, Tereza (Tamara Yevgenyevna) Zhabotinskaya-Kopp, founded a private, female secondary school in Odessa.