Complex sentence: The tranquil property was formerly owned by Edward L. Doheny and his wife, the Countess Estelle Doheny, who made their fortune in oil; the Chester Place residences were built at the turn of the century by Judge Charles Silent.
Split into simpler sentences: The tranquil property was formerly owned by Edward L. Doheny and his wife, the Countess Estelle Doheny, who made their fortune in oil. The Chester Place residences were built at the turn of the century by Judge Charles Silent.