Perhaps this will be a help.My relative was Mary Martha LOOKER born 23 Sep 1853, married in Ontario to Archibald Weller LONGHURST, died 8 Apr 1936.I have been able to find LONGHURST relatives before and after these dates but not LOOKER which might also be LUKER.
I did find a Thos. Alfred LOOKER on the Federal Census of 1871 (Ontario Index) on the Internet.They listed Thos Alfred briefly as male, 23 years old, birthplace Ontario, Church of England, Anglican, Origin English, Occupation Butcher, District Simcoe South (041), Subdistrict Innisfil (G) District 3, Page 3, Microfilm reel C-9961.
I am thinking that Thos Alfred (born abt 1848) could be the older brother for my Mary Martha.The husband for Mary Martha was a farmer in Oro in 1877 but in or about 1882 had become a butcher in Barrie.
It would seem that this Thos Alfred LOOKER could be a grandparent or other relative to the LOOKER you are seeking.