Rose, I asked a helpful lady if she'd look for a headstone inscription for your Walter Charles Collister and Edith. She sent this:

Rushen 1926 Yard
#392
In loving memory of
WALTER CHARLES COLLISTER
dearly loved husband of EDITH
died 9th Oct 1963 aged 70 years
also the above
EDITH COLLISTER
died 22nd December 1976 aged 74 years

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This suggests that Edith was born in 1902 and died in 1976. Of course, it might be wrong.

Where did you get the information that she was born 18th October 1905 and that she died in December 1979 ? I'm assuming that you've never seen her birth certificate. Have you seen a death certificate ? Could it be that someone in the family knew that her birthday was 18th October, and they thought they knew her age, but that Edith had knocked 3 yrs off her age throughout her adult life ?

Have you got a copy of her marriage certificate ? That should give her father's name and occupation.

Jean C