This has been an interesting subject in that I have found some information I didn't expect, but haven't found some of the basic information I did expect.
For example, I can only find 2 of 6 in the 1891 census; 2 of 6 in 1901; and 2 (maybe 3) in 1911.
Your 1901 census entry may be my Ada, but by my records she was b. 20 Mar 1881, so 4 Jun would be the wrong woman.
I haven't found obit's for any, yet. What I did find interesting is the names of witnesses on marriage certificates. Tracing those helped to find the other siblings. If names of witnesses are correct then I believe I am looking for an Ada CLARK of Hamilton. Again, just a clue.
I'll followup with the other information you found and see where it leads.