Wilhelm married Emilie B. C. Pergande 17 Jan 1886, Chicago, Cook, Illinois, USA. Emilie (daughter of Johann Pergande and Johanne Wilhelmine Caroline Schneider) was born 20 Dec 1865, Groß Rambin, Belgard, Pommern; died 8 Jan 1955, Elgin, Cook, Illinois, USA. [Group Sheet]

1. Elsa Adel Prochnow was born 17 Oct 1886, Chicago, Cook, Illinois, USA; died 29 Dec 1970, Des Plaines, Cook, Illinois, USA.
2. William Arthur Prochnow was born 22 Nov 1887, Skokie, Cook, Illinois, USA; died 20 Jun 1970, Arlington Heights, Cook, Illinois, USA; was buried 23 Jun 1970.
3. Lillian Prochnow was born 14 Dec 1889, Cook, Illinois, USA; died 30 May 1980, Arlington Heights, Cook, Illinois, USA.
4. Alfred John Prochnow was born 8 Apr 1891, Skokie, Cook, Illinois, USA; died 4 Feb 1984, Cook, Illinois, USA.
5. Erna E. Prochnow was born 20 Sep 1892, Cook, Illinois, USA; died 3 Jun 1981.
6. Lydia Prochnow was born 22 Jun 1894; died Bef 1900.
7. Edwin Prochnow was born 13 Apr 1896, Skokie, Cook, Illinois, USA; died 8 Jan 1973, Milwaukee, Milwaukee, Wisconsin, USA.
8. Elizabeth Prochnow was born 6 Jun 1902; died 1903.
9. Emily E. Prochnow was born 6 Jun 1902, Cook, Illinois, USA; died 30 Jan 1982, Arlington Heights, Cook, Illinois, USA.
10. Ellinor Esther Prochnow was born 6 Jun 1902, Cook, Illinois, USA; died 18 Dec 1985.
11. Edna A. Prochnow was born 4 Oct 1903, Cook, Illinois, USA; died 25 Aug 1992, Mount Prospect, Cook, Illinois, USA.
12. Esther H. Prochnow was born 1 Nov 1905, Niles, Cook, Illinois, USA; died 14 Jan 2004, Waukegan, Lake, Illinois, USA.
13. Albert H. Prochnow was born 9 Oct 1908, Northbrook, Cook, Illinois, USA; died 28 Sep 2000, Palatine, Cook, Illinois, USA.