Upper class family and relatives based around Murdoch Haddon MacLean, Vice President of the Harris Trust and Savings Bank of Chicago (and son-in-law of its founder, N.W. Harris) and his wife, Pearl Harris MacLean.

Murdoch Haddon MacLean was born in Uigg, Prince Edward Island, Canada on December 27, 1872. He was the son of Rev. John and Christina MacLean. He graduated from Acadia College, Nova Scotia in 1892, and did post-graduate work at the University of Chicago and John Marshall Law School. He then worked in the Office of the Superintendent of Buildings and Grounds at the University of Chicago until 1911. He was involved in the Eleanor Association, a group founded by Ina Robertson in 1898 to assist young working women, where he met Pearl Harris, and they married on June 22, 1910 at the Harris family home, Wadsworth Hall, in Lake Geneva, Wisconsin.

MacLean, often known as M.H. or just Haddon, joined his in-laws' business and became the Vice President and Director of the Harris Safe Deposit Company. In 1916 he was appointed Secretary of the Harris Trust and Savings Bank, starting in the Trust Department, and was elected Vice President in 1922. In 1926 he moved over to the Corporation Department. He was also a Director of the bank, and a Vice President and Director of the N.W. Harris Company. He retired from the bank in 1942. In addition, he served as a trustee of the YMCA and of Wesley Memorial Hospital.

Pearl Emma Harris (often called Polly) was born on October 17, 1882 in Evanston Illinois, daughter of N.W. and Emma Susan Gale Harris. She was educated at the University of Chicago and in Paris. She was a founder of the Evanston Garden Club, a member of the Colonial Dames, and was active in Red Cross and civilian defense work.

Haddon and Pearl had three sons: Haddon Harris MacLean (1912-1983), John Bartlett MacLean, (1914-1939), and Gordon Gale MacLean (1916-2004). John B. MacLean died of pneumonia at the age of 24, while a senior at the University of Chicago.

Haddon's sister, Annie Marion MacLean, was the second woman to receive a PhD from the University of Chicago, in 1900. She was assistant professor of sociology at the University of Chicago from 1903 to 1934, teaching sociology through correspondence courses. She was also the author of numerous books on sociological topics, often focusing on the theme of women in the workplace.