According to the 1900 Census, Mary was born in Aug 1853 in Bohemia; she had 8 children, 6 still living. With her are son William born 1876 in Bohemia, Joseph 1883 indiana, John 1884 Indiana, daughter Jozefa 1886 in Indiana, daughter Anna 1887 in Indiana. That leaves one living child unaccounted for, as well as 2 that died. She says that she and William emigrated in 1881.
Here is info from John Sr.’s naturalization petition (found on this websitehttp://www.rootsweb.ancestry.com/~instjose/LadewskiPapers/Lu...
JOHN JOSEPH DIETZ SR
Nat Intent Vol 3 pg 302: filed 8 Nov 1882. Born Austria. Emigrated port of Hamburg, arrived port of New York 5 May 1881. Wife Mary.
John J b] 10 Oct 1884
Josephine b] 6 Dec 1886