William married Margaret Strain on 15 Sep 1852 in Toronto, Ontario, Canada. Margaret (daughter of Joseph Strain and Elizabeth Little) was born on 17 Nov 1833 in Co. Monaghan, Ireland; died on 9 Apr 1903. [Group Sheet] [Family Chart]

1. Mark Armstrong was born on 24 Oct 1853 in Markdale, Ontario, Canada; died on 5 Sep 1933 in Markdale, Ontario, Canada.
2. Elizabeth Armstrong was born on 1 Aug 1855 in Markdale, Ontario, Canada; died on 9 Nov 1935 in Toronto, Ontario, Canada; was buried in Markdale, Ontario.
3. Margaret Jane Armstrong was born on 18 Dec 1857 in Markdale, Ontario, Canada; died on 19 Dec 1934 in Edmonton, Alberta, Canada; was buried in Edmonton Cemetery, Edmonton, Alberta, Canada.
4. William A. Armstrong was born on 12 May 1860 in Markdale, Ontario, Canada; died on 3 Sep 1907.
5. Sarah Armstrong was born in 1862 in Markdale, Ontario, Canada; died in 1883 in Markdale, Ontario, Canada.
6. Sophia Armstrong was born in 1865 in Markdale, Ontario, Canada; died on 25 Sep 1936 in Markdale, Ontario, Canada.
7. Teresa Ellen 'Nellie' Armstrong was born on 20 Aug 1867 in Markdale, Ontario, Canada; died on 10 Jun 1942 in Markdale, Ontario, Canada.
8. Joseph Rusk Armstrong was born on 31 Jul 1869 in Markdale, Ontario, Canada; died on 9 Sep 1929 in Markdale, Ontario, Canada.
9. George Whitfield Armstrong was born in 1872 in Markdale, Ontario, Canada; died on 16 Mar 1933 in Peterborough, Ontario, Canada.
10. Charles Edgar Armstrong was born on 1 May 1876 in Markdale, Ontario, Canada; died on 8 Jun 1948.
11. Herbert James Armstrong was born in 1878 in Markdale, Ontario, Canada; died on 3 Jun 1940 in Markdale, Ontario, Canada.