Complex sentence: Her father, Grigory Krasko, was a concertmaster of the Moscow Philharmonic Orchestra, her mother, Olga Kondratieva, is a pianist and a professor in Gnessin State Musical College.
Split into simpler sentences: Her father, Grigory Krasko, was a concertmaster of the Moscow Philharmonic Orchestra. Her mother, Olga Kondratieva, is a pianist and a professor in Gnessin State Musical College.