Does this new info help?
Catharine and John COLLIER were married in Ilkley at the Parish Church, Dec 24th 1875. In 1891 we know that Catharine was with her sister Mary Young (mistranscribed Mary B Fanny on the census) in Lockwood. In 1881, the Youngs were in Ilkley.
Since John died in 1881, and Isabel Beatrix was born in 1883, is it possible that Catharine was living with the Youngs when Isabel was born?
Alternately, perhaps the Youngs had already moved to Lockwood, and she was living with them there, as George Edwin's death in 1885 was registered in Dewsbury.
Therefore, I think we shall find Isabel Beatrix, hopefully as a COLLIER, in the registers for Jun (maybe Sep) 1883 in either Lockwood (reg Dewsbury) or Ilkley (reg Wharfedale).
Does anyone have access to Parish Records for Lockwood or Ilkey for the period 1883-1885?
I have tried, as best I can, to track down all of Catharine Hill COLLIER's brothers and sisters for the period concerned. I cannot find anyone who could be Isabel, but I haven't been able to locate all of her brothers yet. I am still missing (all born in Leeds) Arthur HILL (b 1845), Edwin HILL (b 1849), and Charles HILL (b 1858) on the 1891 census.
Back to work....
Rupie