The 1900 census suggests that John (Janos) may be older than you think:
Youngstown, Mahoning County, Ohio
Kosher, John, Head, born March 1868, aged 32, married, 1 year, born Hungary, parents b. same, immigrated 1896 (four years in country), laborer Kosher, Mary, Wife, born June 1881, aged 18, married, 1 year, 1 child born/living, born Hungary, parents b. same, immigrated 1899
Kosher, Catherine, Daughter, born June 1900, aged 1 month, born Ohio
I did find a record for a Maria Kalna, aged 18, who arrived aboard the SS Karlsruhe from Bremen on October 1, 1898, bound for her sister in Youngstown. Last of Haraszt.