Cook, Willis C.. M. D., was born in Bergen, Genesee county, June 25, 1832. Was educated in the common schools and in 1883 entered the medical department of the Niagara University of Buffalo; in 1884 he entered the Northwestern University of Ohio, medical department, and in 1885, graduating from the Toledo Medical College in the same year. He located in Brockport where he engaged in the practice of his profession, and is now enjoying a very large practice. In 1855 he married Adeline Hawks, who died in 1857; second he married Mary, daughter of Philip Williams of Paw Paw, Mich., and their children are Francis W., Karl R., Jay W., Curtis L. and Lenoir. Dr. Cook served during the late war as follows: First enlisted in November 16, 1861, as a sergeant in Co. K, 13th Mich. Vol. Inf., and was discharged at Detroit for disability November 3, 1862; enlisted again as veterinary surgeon 9th Mich. Cav., and served till the close of the war, being discharged at Lexington, N. C., July 21, 1865. His father, Curtis Cook, was a native of Pompey Hill, Onondaga county, and settled in Bergen in an early day, later moved to Clarendon, Orleans county, where he died December 1, 1883, aged eighty-one years; he married Betsey Snow Brown, daughter of Elijah Brown of Vermont, who was one of the first three white men to settle in Byron; took a farm where he died in 1852, at the age of eighty-six years. Lemuel Cook, grandfather of Willis Cook, was a native of Norwich, Conn., and served in the Revolutionary war under General Washington, who personally signed his discharge papers. After the war he settled at Pompey Hill, and later moved to Bergen, from there he went to Clarendon, where he died at the advanced age of one hundred and seven years, the only Revolutionary soldier known to be alive at that date, March 6, 1863. Betsey Snow, wife of Curtis Cook, still lives on the old homestead in Clarendon at the age of ninety-one years.

From Landmarks of Monroe County, NY
by William F. Peck (1895)
Part III, p. 11

Dr. COOK is a native son of the Empire state, his birth having occurred in Bergen, Genesee County, June 25, 1832. His paternal grandfather, Lemuel COOK, was a native of Norwich, Connecticut, and served in the Revolutionary war under General WASHINGTON, who signed his discharge papers. Following the war the grandfather located at Pompey Hill, in Onondaga County, while later he took up his abode in Clarendon, where he died at the very extreme age of one hundred and seven years, the only Revolutionary soldier known to be alive at that date, March 6, 1863.
The father, Curtis COOK, was a native of Pompey Hill, Onondaga County, and at an early day settled in Bergen, while later he removed to Clarendon, where he was engaged in farming throughout his entire active business career, owning a farm of one hundred and twenty acres, situated near the old Root schoolhouse. He wedded Betsy Snow BROWN, a daughter of Richard BROWN, of Vermont, he being one of the first three white settlers of Byron, Genesee County, locating on a farm there, where his death occurred in 1852, when he had reached the advanced age of ninety-six years. Both of the parents are now deceased, the father having been called to his final rest December 1, 1883, when he had reached the age of eighty-three years, while the mother survived for a few years and passed away on the old homestead, being ninety-one years of age at the time of her demise. The father gave his political support to the republican party and supported the Sweden Baptist church. His family numbered six children: Henry, a resident of Coldwater, Michigan; Willis C., of this review; Rosetta, who is the wife of Henry VANDEBURG, a farmer of Sweden township, Monroe County; and Nancy, William F. and Whitney, all of whom have passed away.
Dr. COOK, the second in order of birth in his father's family, was reared under the parental roof, assisting his father in the duties connected with the operation of the old homestead property and acquiring his early education in the Root school. At the outbreak of the Civil war, loyal to his country, he offered his services to the government, enlisting November 16, 1861, as a member of Company K, Thirteenth Michigan Volunteer Infantry, and was discharged at Detroit on account of disability on the 3d [sic] of November, 1862, with the rank of sergeant. He re-enlisted as a veterinary surgeon in the Ninth Michigan Cavalry and served in that capacity until the close of the war, being discharged at Lexington, North Carolina, July 21, 1865.
Following his return home from the war he once more took up his abode in Monroe County but eventually decided upon the practice of medicine as a life work and to that end, in 1883, entered the medical department of Niagara University, at Buffalo, where he studied for one year, subsequent to which time he continued his studies in the Northwestern University of Ohio, and in 1885 entered the Toledo Medical College, from which he was graduated in that year. He then returned to New York and located in Brockport, where he has since been engaged in practice. He has ever been a student of the science of medicine and keeps abreast with the advancement which is continually being made in the medical profession through research and investigation. He is genial and courteous in manner, devotedly attached to his work, and therefore constant demand is being made upon his services.
Dr. COOK has been twice married. His first wife was Miss Adeline HAWKS, whom he wedded in 1855, and who died two years later. His present wife bore the maiden name of Mary E. WILLIAMS, and was born at Paw Paw, Michigan, a daughter of Philip and Polly WILLIAMS, farming people of that place. By her marriage Mrs. COOK has become the mother of five children: Francis W., who resides on a farm near Clarkson, New York; Carl R., who is engaged in mining and the real-estate business in the City of Mexico, where through his operations he has accumulated a capital of three million dollars; Lenore V., the wife of Charles H. PHILBROOK, of New York City; J.W., who resides in Rochester, where he is engaged in the drayage business; and Curtis L., a resident of Chicago.
Like his father, the Doctor gives his political support to the republican party. He has served as health officer for ten years and was coroner's physician for two years. His fraternal relations are with the Masonic order. Like the older generations of the COOK family the Doctor has rendered valuable aid to his country, while his brother, J.W., served in the Spanish war, and his brother Frank was with General MILES fighting the Indians in the Rose Bud reservation. His life has been one of continuous activity and that his professional labors have been crowned with a gratifying measure of success is indicated by the fact that he today enjoys a large and lucrative patronage not only in the City of his residence but throughout the surrounding districts as well.

From History of Rochester and Monroe County New York From the Earliest Historic Times to the Beginning of 1907, by William F. Peck (1908), pages 476 & 479