In the early 1960s, McDonald's really began to take off. The growth in U.S. automobile use that came with suburbanization and the interstate highway system contributed heavily to McDonald's success. In 1961 Kroc's conflict over the vision of the company with the founding brothers had grown to an unbearable extent, and he asked them how much money they wanted to leave their business to him entirely. The brothers asked for $2.7 million (about $21.6 million in today's dollars), which Kroc did not have. Harry J. Sonneborn was able to raise the money for him, and Kroc bought the founding brothers out. This purchase laid the groundwork to positioning the company for an IPO and furthering the aim at making McDonald's the number one fast-food chain in the country. The exact process of how the company was sold is not well-recorded; it is depicted as hostile takeover sides Ray Kroc in the movie "The Founder" but that portrayal is disputed, and interviews of the time speak of a more voluntary transition.