Hi Maggie
Mabel wrote her will in 1958, but Edith had died 5 years earlier. The Elizabeth Catherine Clegg (for whom Laura was working ) mentioned in Mabel's will , was the widow of Mabel and Harriet's older brother, John Clegg (1881-1933).
She lived at "The Vollan", Albany Road, Douglas, at the time she wrote her will in December 1969, and she still lived there when she died on 15th September 1972.
If Laura was still alive in Sept 1972, then she was the fortunate recipient of £1000:

2. I bequeath to my companion housekeeper Miss Laura Starkey the sum of
ONE THOUSAND POUNDS absolutely.

I imagine that "The Vollan" would also be / have been a pretty grand house.
Edith, Mabel, John and their other brother, William, were my grandpa's first cousins---the well-heeled branch of the family.
Jean