How do you know that the Bertha Cottam in 1901 is the correct one?
There are baptisms for:
Bertha Cottam 26 September 1883 Oldham, Lancashire, England parents John and Mary
Bertha Cottam 13 June 1894 St Anne's Church, Haughton, Lancashire, England parents Harrison and Elizabeth
Bertha Cottam 18 June 1884 Bolton, Lancashire, England parents Thomas and Mary Jane
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