Minnie and her sister Anna were born in Mississippi; their parents died poor when the girls were very young. Anna remained in Mississippi with an aunt. Minnie went to Dallas, Texas, to visit an uncle, a Dr. Williams, who adopted her. In 1886 he sent her to Boston to attend the Conservatory of Elocution. About the time she was graduated her uncle died, leaving to her property in Fort Worth valued at about $20,000. After a brief visit with another uncle, the editor of the Methodist Christian Advocate, Minnie took her sister Anna to Dallas, where Anna entered school. Minnie, the elder sister, embarked on a teaching career. She taught elocution in Denver and at Midlothian, Texas. Presently she turned up in Mississippi and displayed a photograph of a certain young man named Harry Gordon in whom she was interested because he was "handsome, wealthy, and highly intelligent." He was of course Dr. Holmes. In March of 1893 (she was in her early twenties) she went to Chicago and soon wrote to her aunt that she had married her friend and that she was very happy.

It is believed that Holmes committed his first murder for her. When she arrived at the castle he was living with Mrs. Conner. Minnie, an extremely attractive, fresh-faced young girl, was jealous. Holmes killed Mrs. Conner and her eight-year-old daughter, it is thought.

he used her Fort Worth real estate in some of his schemes, though probably without her knowledge. That she was his mistress there can be little doubt. Yet she played a strange role for a mistress on at least one occasion: she served as his witness when he married his third (and last) wife.

A few months after Minnie arrived at the castle she invited her younger sister Anna to join her. Anna left Texas at the end of June, 1893. On July 4th she wrote happily to her aunt that "sister, brother Harry, and myself" would leave the next day for Europe, where Anna might remain to study art. She added, "Brother Harry says you need never trouble any more about me, financially or otherwise; he and sister will see to me." This proved prophetic: Anna Williams never was seen or heard from again.

Holmes fled from Chicago. His next public appearance was in Denver where, on January 17, 1894, he married his third wife, Georgie Anna Yoke, with Minnie Williams as a witness. (It will be recalled that Minnie once had taught school in Denver.

Soon after that, she disappeared, and he confessed that he murdered her in Denver Colorado before he was executed by hanging.