In addition to her political work, Arneill was an accomplished golfer, winning the Colorado Women's Open Championship in 1931.

[5] Her father, Louis H. Porter, was a corporation lawyer and manufacturer, and her uncle, Schuyler Merritt, was a long-serving member of Congress and mentored her.

[1][5] During her time at Yale, she met James Rae Arneill Jr., a medical student from Denver, Colorado.

[6] In September 1938, Arneill was elected as the first president of the newly established National Federation of Women's Republican Clubs of America during a meeting held in Chicago.

[7] The federation, directed by Marion Martin, assistant chairman of the Republican National Committee, aimed to expand its membership to 500,000 by the 1940 election.

Its objectives included educating women on political issues, supporting Republican candidates, and promoting principles such as freedom, equality, and justice.

[8] Prior to this position, Arneill had organized the Independent Coalition of American Women in Colorado in 1936, where she helped form 23 clubs with approximately 3,000 members.

Her experience in Colorado contributed to her selection as president, where she focused on increasing women's participation in the Republican Party and promoting their involvement in political activities.

[10] During the assembly, Arneill introduced Wendell L. Willkie, the Republican Presidential nominee, at a mass meeting held in the Olympia Auditorium.

[3] On Tuesday, May 1, 1934, their son was born at the Harkness Pavilion, located at 70 Haven Avenue in New York City.