Greenway arranged for Morris to become an apprentice at the shipping and banking firm of Philadelphia merchant Charles Willing. In 1750, Robert Morris, Sr. died from an infected wound, leaving much of his substantial estate to his son. Morris impressed Willing and rose from a teenage trainee to become a key agent in Willing's firm. Morris traveled to Caribbean ports to expand the firm's business, and he gained a knowledge of trading and the various currencies used to exchange goods. He also befriended Thomas Willing, the oldest son of Charles Willing who was two years older than Morris and who, like Morris, had split his life between England and British North America. Charles Willing died in 1754, and in 1757 Thomas made Morris a full partner in the newly renamed firm of Willing Morris & Company.