Dennis Oscar Donovan was a son of Peter Donovan and Julia Wholey.
Katherine Veronica Garvey was a daughter of Timothy Garvey II and Margaret Lyons.

Denis Oscar Donovan and Katherine Veronica Garvey married on 19 Apr 1887 in Clermont, Fayette, Iowa.

Children:

Margaret Ellen Donovan (1888 - 1952). married Walter Joseph Worth

Ethel Julia Donovan (1890 - 1970).  married William Eugene Kinney

Mary Donovan (1892 - 1892)

Katherine Veronica Donovan (1894 - 1983).  married Albert Alton Kuhle

John Joseph Donovan (1896 - 1950) . married Eleanor Donovan

Marie Celeste Donovan (1899 - 1952).  married Arthur John Cashel

Genevieve Erma Donovan (1901 - 1965)

Madeline Agnes Donovan (1903 - 1980).  married Winfield Clifford Clark

Dennis Gerald Donovan (1904 - 1978)

Alice Ramona Donovan (1907 - 1907)

Obituary from the Argus Leader dated 13 Dec 1928 page 20:

DENNIS DONOVAN, SR.
Funeral services for Dennis Donovan, sr.. 73, 219 North Spring ave., who died Wednesday at his home, will be held from St. Joseph's cathedral Saturday morning at 8:30 o'clock. Burial will be made in the Catholic cemetery.
The deceased was born at Bradford. Vt., June 18, 1856, receiving his early education at Littleton, N. H. He came west in 1881, locating at Streetor, Ill. After two years there he came to Sioux Falls in 1883. On April 10, 1886, he was united in marriage to Catherine Garvey of Clermont. Ia.. returning to Sioux Falls with his bride on June 15, 1886. To this union were born ten children, two of whom died in infancy. Mrs. Donovan preceded her husband in death, January 15, 1925.
In 1886, Mr. Donovan engaged in the meat market business on Main avenue, between Tenth and Eleventh streets. In 1888 he sold his business to Tom Archer and became connected with Wider & Blum Hide company, being connected with them until 1899 when he became affiliated with Bolles and Rogers, with whom he was connected at the time of his death. He was a pioneer traveling man in South Dakota, being on the road in this state for over 20 years, before his eyesight failed him and compelled him to leave that type of work.
Mr. Donovan is survived by six daughters and two sons. The daughters are Miss Genevieve Donovan, Sioux Falls; Mrs. W. J. Warth, St. Louis; Mrs. W. E. Kinney, Salem: Mrs. A. A. Kubee, Sioux City; Mrs. A. J. Cashel, Sioux Falls; and Mrs. W. C. Clark, Canistota. The sons are Dennis Donovan, jr., and J. J. Donovan, Excelsior, Minn, He is also survived by two brothers, J. M. Donovan, Omaha, and John J. Donovan, Gary, Ind., and one sister, Mrs. A. J. Parteus, Berlin, N. H., all of whom will be here for the funeral.
Mr. Donovan was a member of St. Joseph's cathedral parish, the Modern Woodmen of America, and the Illinois Commercial Men's association.

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