HI Danone
I spoke to "my" Mabel this afternoon and it seems she is "the one" you're looking for!

She confirmed that Vera was Albert's sister and that her maiden name was WESTON.
Mabel, after Albert's death, moved to a bungalow on St Mary's Avenue and then later into St Mary's Court (not Fairfield Court, which is the old people's flats on Ashburton Rd, opposite the school.)
Mabel was thrilled to bits to think someone was looking for her and can't wait to know more details! If you would like to send me further details in a pm about yourself and your family, if you don't want to place personal details on here, I will pass them on. Perhaps you and Mabel may then want to meet up.
Hope to hear from you soon!

Jan