On October 29, 1890 as Mary Butterworth, she married Haughwout Howe at the District of Columbia.
He died on October 30, 1890.
On Tuesday, February 14, 1899, she married George Heazelton of San Francisco at the home of Dr. St. John Roosa at New York City.

Mary Butterworth Heazelton was born to Quaker parents in Mainville, Ohio. Her father was Representative Benjamin Butterworth, a Republican, who died in 1898. She came to the District of Columbia in 1878 when her father was elected to Congress. She was married to Haughton [Haughwout] Howe, associated with New York and District newspapers. Her second husband, George Heazelton, a New York and San Francisco businessman died in 1914 [1910]. She was a member of the Chevy Chase Club and a former member of the Congressional Country Club. She resided at the Wyoming Apartments at 2022 Columbia Road Northwest. She died at age 84 on Monday, October 18, 1948 in Hartford, Connecticut where she had traveled for treatment of an illness.
Source: The Evening Star, Monday, October 18, 1948.

New York Herald Friday, October 31, 1890
Wedded One Day, Died The Next
Sad Death of Mr. Haughwout Howe, Who Married Miss Butterworth on Wednesday
His Bride Of A Day
She Held His Hands in Her Tender Clasp Until the Last Summons Came
Interment At Woodlawn
[From Our Regular Correspondent]
Herald Bureau
Corner Fifteenth And G Streets Northwest, Washington, October 30, 1890
Howe-Butterworth. At Washington, October 29, by the Rev. Dr. Bartlett, Mr. Haughwout Howe, United States Dispatch Agent at New York, to Miss Mary Butterworth, daughter of Benjamin Butterworth, of Cincinnati.

Howe. At Washington, October 30, of endocarditis following acute rheumatism, Mr. Haughwout Howe, United States Dispatch Agent at New York. Funeral from 1016 Vermont Avenue, at ten AM Friday. Interment at Woodlawn Cemetery, New York.

These two simple announcements tell with pathetic earnestness the story of Haughwout Howe's last day on earth and the unusual circumstances which, in the brief space of twenty-one hours made his wife a bride and a widow. Almost at the very instant that, according to their long-made plans they would have been standing in the Friends' Meeting House, plighting their faith in the presence of their friends, the bridegroom passed away to his eternal account. Their marriage was to have been today at twelve o'clock. Fifteen minutes past the hour he had breathed his last.

The Widow
Mrs. Howe as Miss Butterworth has been not only a striking figure in society and a general favorite everywhere her accomplishments and good looks always brought her to the front, but she has been besides the idol of her family circle. Since her entry in society, a few seasons back, she has had no end of suitors and attention. At home, she was a devoted daughter to the best of parents and the constant companion of her three young brothers.

With a decided talent for the stage, she has been the life of many of the most successful amateur theatrical entertainments. She is a skilled horsewoman and fond of outdoor sports. Representative Butterworth was averse to her marriage with Mr. Howe, but she won him over at last and all that doting parents could do was in progress to have made this, her wedding day, as happy as possible.

Mrs. Harrison, Attorney General Miller and family were to have been guests at the wedding breakfast and every notable acquaintance the family had was represented by a handsome wedding gift. A thousand announcement cards were to have been sent all over the country in tomorrow's mail.

The club chambers, where the death occurred adjoin the elegant quarters of the Metropolitan Club, the most exclusive body in capital clubdom. Many of the leading citizens, officials, army and navy officers and others in private life, make up its membership list. In the club chambers its members are housed in tasteful luxury. The rooms are small, but well-appointed and the outlook is over the most desirable section of the city.