I'm working on my family's most frustrating 'brick wall':

I was wondering if anyone has any information, especially on the possible parents of a John GRANT who was born in either c.1791 "of Charlottenburg Twp., Ontario, Canada"(according to IGI of his daughter's christening) or c.1798 in "Upper Canada". He died in November 1869 and is buried in St.Andrew's Churchyard in Williamstown, Glengarry Co., Ontario, Canada. Family legend says that this John is related to the well-known John Grant "of Duldreaggan, Glenmoriston" or John "Big John the Robber" Grant (John "of Duldreaggan" and "Big John the Robber" may be the same person).
His wife, Mary was born either c.1795 "of Charlottenburg Twp., Ontario, Canada"(according to IGI of her daughter's christening) or c.1797 "in Scotland" (depends on whether you believe the IGI or the census), and her maiden name was most likely GRANT as well. She was still living in 1871, as she is found on the 1871 census living in Charlottenburg Twp,Glengarry Co., Ontario, Canada.

They had a daughter who went by the name 'Jane' but is also named 'Sarah Jane' in some records. She was christened as 'Jane Grant' on 22 October 1823 at St.Andrew's Church in Williamstown, Glengarry Co., Ontario, Canada. According to the 1881 census though, she was born c.1827. She died on 5 October 1893 and is buried with her husband at St.Andrew's Churchyard in Williamstown, Glengarry Co., Ontario, Canada. She married James Alexander "Sandy" DOW in 1845.
On the 1881 census, James & Jane Dow are living in District 99, Sub-District A, Division 2 of Charlottenburg, Glengarry, Ontario.
On the 1871 census, it shows James Dow (husband of Sarah "Jane" Grant) as being born in Scotland (?!) in 1820 and living in Division 1 of Charlottenburg Twp in Glengarry county and it shows his mother-in-law, Mary Grant (wife of John Grant) as being born in Scotland in 1791 and living in Division 1 of Charlottenburg Twp in Glengarry county (I think I remember discovering that Mary lived with her daughter and son-in-law in 1871).
It would be great to see what the 1851 census shows for all of these individuals (especially John & Mary Grant!).

Any information on these families or even 'geusses' would be very helpful!!

Thanks!

Maggie Barron