Harriet Lerner, Ph.D., (born November 30, 1944) is a clinical psychologist and a contributor to feminist theory and therapy.
 From 1972 to 2001 she was a staff psychologist at the Menninger Clinic in Topeka, Kansas and a faculty member and supervisor in the Karl Menninger School of Psychiatry.
 During this time she published extensively on the psychology of women and family relationships, revising traditional psychoanalytic concepts to reflect feminist and family systems perspectives.
 Her younger son is the National Book Award-nominated poet and novelist Ben Lerner.
 Her eldest son, Matt Lerner, is the co-founder of Walk Score.
William Walter Menninger (born October 23, 1931), known by his peers as "Dr. Walt", is an American psychiatrist in the third generation of the Menninger family, which has run the Menninger Foundation since 1925.
 He served as dean of the Karl Menninger School of Psychiatry and Mental Health Science and he was the CEO of the Menninger Clinic from the 1993 to 2001.
 During his tenure as CEO, the clinic began negotiations to move to from Topeka, Kansas, to Houston, Texas, where it is affiliated with Baylor College of Medicine.
Charles Frederick Menninger (11 July 1862 – 28 November 1953) was a physician who co-founded the Menninger Foundation with his sons, Karl and William.
Karl Raphael Herder (2 November 1816 - 10 June 1865) was the older son of Bartholomäus Herder.
 Karl ran the commercial side of the Verlag Herder business, while his younger brother, Benjamin Herder, took charge of the publishing department.
 Karl retired in 1856.
 His brother assumed total control of the company.
The Menninger Foundation was founded in 1919 by the Menninger family in Topeka, Kansas, and consists of a clinic, a sanatorium, and a school of psychiatry, all of which bear the Menninger name.
 In 2003, the Menninger Clinic moved to Houston.
 The foundation was started by Dr. Charles F. Menninger and his sons, Drs. Karl and William Menninger.
Claudia Zaslavsky (January 12, 1917 – January 13, 2006) was an American educator and ethnomathematician.
 She advanced the study of the links between mathematics and world cultures, especially with her pioneering book "Africa Counts", that extended to Africa the work of Karl Menninger about mathematics in ordinary life in other parts of the world.
 She also worked to advance multicultural mathematics teaching with books and articles and by personal activity.
 Her son Thomas Zaslavsky is a mathematician in the U.S. and her son Alan Zaslavsky is a statistician at Harvard Medical School.
William Claire Menninger (October 15, 1899 – September 6, 1966) was a co-founder with his brother Karl and his father of The Menninger Foundation in Topeka, Kansas, which is an internationally known center for treatment of behavioral disorders.
Karl Augustus Menninger (July 22, 1893 – July 18, 1990) was an American psychiatrist and a member of the Menninger family of psychiatrists who founded the Menninger Foundation and the Menninger Clinic in Topeka, Kansas.
Karl Menninger (October 6, 1898 – October 2, 1963) was a German teacher of and writer about mathematics.
 His major work was "Zahlwort und Ziffer" (1934,; English trans., "Number Words and Number Symbols"), about non-academic mathematics in much of the world.
 (The omission of Africa was rectified by Claudia Zaslavsky in her book "Africa Counts".)
The Chicago Institute for Psychoanalysis is a center for psychoanalytic research, training, and education that is located on Michigan Avenue in downtown Chicago.
 The institute provides professional training in the theory and practice of psychoanalysis and psychotherapy.
 It was founded in 1932 by Franz Alexander, a pioneer in psychosomatic medicine at the Berlin Psychoanalytic Institute, who moved to Chicago at the invitation of Robert Maynard Hutchins, then president of the University of Chicago.
 Notable psychoanalysts that have been associated with the institute include Karl Menninger, Karen Horney, Thomas Szasz, Therese Benedek, Hedda Bolgar, Roy Grinker, Maxwell Gitelson, Louis Shapiro, Heinz Kohut, Arnold Goldberg, Jerome Kavka, Frank Summers, and Michael Franz Basch.

Question: Which Menninger brother was older, William or Karl?
Answer: Karl Augustus Menninger