I think the following may be [ hopefully ]your Cudney family.
I don't know if this is the same Wm Cudney as on 1861 but age is close and he is still in Elgin. Only one I could find on the census.
1911 census Bayham, Elgin East
Wm, b Nov 1847, 64, Ontario, Anglican, gentleman
Mary, wife, Jan 1860, 50, Ont
Maud, dau, Oct 1885, 26,Ont, milliner
Annie, dau, Mar 1886, 25, Ont, milliner
1901 census Bayham Elgin East
William, 1 Nov 1850, 50, gentleman
Mary, 15 Jan 1859, 42
Maud, 4 Oct 1881, 19
Anna, 30 May 1885, 17
Maria Brightly, lodger, 1 May 1865, 35, school teacher
The birth months are the same but all the birth years are different from 1911 census. Census are notorious for wrong information.
Birth: Maude Cudney, b 4 Oct 1881, Elgin, Wm H Cudney & Mary Thompson.
Didn’t find a birth rego for Anna.
Didn’t find marriage registration for either Maud or Anna.
1871 census Malahide, Elgin East
John, 27, b Ont, farmer
William, 21, b Ont
Margaret, 60, Ont
This Margaret is the same age as Margaret Walker.
On 1881 census Michigan, Henry's wife's name is given as Happy, aged 68. There is no Margaret Cudney on 1881 census in Ontario that I could find. Any chance that Margaret Walker and Margaret Cudney are the same person?
I cannot find either John or Wm on 1881 census but have a look on www.familysearch.org
They always seem to stay in Elgin so maybe they were just missed.
1891 census Malahide Elgin East
John, 40, Ont, farmer
Rossena, 36, Ontario
No children listed.
Did not find any birth registrations for any children for John and Rolena/Rossena.
William H Cudney, 27, b Niagara, living Port Burwell, ship calker, s/o Joseph & Margaret Cudney married Mary Thompson, 20, Port Burwell, same, d/o William & Mary Thompson, witn: David & Sarah McNe?lie, both of Port Burwell, 22 May 1878, Bayham Elgin County, Registration # 002229.
John Cudney, 28, b Niagara, living Malahide, s/o Joseph & Margaret Jane married Rolena Secord, 19, Seneca, Malahide, d/o William & Susan, witn: Edson & Martha Jane Secord both of Malahide, 29 Aug 1874, St Thomas, Elgin County, # 001591.
These have the same parents.
William H Cudney, b 1 Nov 1848, Elgin, retired gentleman, watch repairer and fisherman, s/o Joseph & Margaret Cudney, informant: Mary Cudney, wife, of Port Burwell, burial: Vienna , died 22 March 1920, of apoplexy, Bayham Elgin, # 013752.
John B Cudney, aged 63, died 26 Mar 1907, lot 10 South Gore Malahide, farmer, married, b Lincoln County, died of paralysis/3days, Malahide Elgin, # 009842.http://www.islandnet.com/ocfa/search.php
The above site is an index of headstones. The site will give more information re the cemeteries.
Cudney, Annie, St Lukes Anglican, Vienna, Bayham Elgin, Reference: El-243
Cudney, Mary, same as above
Cudney, William H, as above
No sign of Maud.
There is also a Joseph Cudney buried Dunboyne, Malahide, Elgin, Ref: EL-415.