The Milhous brothers, Richard and Maurice, made their money through a variety of different ventures. They started off by purchasing their own oil fields in the 1930s. From there they expanded into real estate development, finance, insurance and banking services. By 1957 they had become one of the largest independent producers of natural gas in Texas. In addition to these investments they were also involved in various business activities such as timber harvesting and dairy farming. The brothers also opened several restaurants throughout Texas during the mid-1960s which provided further income for them. In later years other businesses interests included ranching and manufacturing operations across multiple states including Oklahoma and New Mexico. It is clear that with hard work and dedication the Milhous Brothers achieved great success for themselves through multiple business endeavors ultimately making them extremely wealthy individuals who continue to inspire many people today!