His family had a history of mental illness. His uncle suffered from religious mania. A brother was confined in a state mental hospital. His sister was diagnosed with a "mental affliction". Three other relatives were diagnosed with mental illnesses and his mother had "aural and/or visual hallucinations".[10][11] His father was a river boat captain and by 1870 was a fertilizer manufacturer.[9] The elder Fish died in 1875 at the Sixth Street Station of the Pennsylvania Railroad in Washington, D.C. of a myocardial infarction. Fish's mother then put him into Saint John's Orphanage in Washington, where he was frequently treated sadistically. He began to enjoy the physical pain that the beatings brought.[12] Of his time at the orphanage, Fish remarked, "I was there till I was nearly nine, and that's where I got started wrong. We were unmercifully whipped. I saw boys doing many things they should not have done."
By 1880, his mother had a government job and was able to remove Fish from the orphanage. In 1882, at age 12, he began a relationship with a telegraph boy. The youth introduced Fish to such practices as urolagnia (drinking urine) and coprophagia (eating feces). Fish began visiting public baths where he could watch other boys undress, and spent a great portion of his weekends on these visits.[12] Throughout his