25th: How many POVOAS wives? An explosive mix

Cousin Harry shared a certificate with me as he thought I'd be interested in the FAIRBAIRN on it (as well as one of our mutual WIGHTs).
After processing it I checked the third birth on the page and realised that is was for another of our WIGHT relations, the birth of Elizabeth Jane WHITSON, dtr of Elizabeth WIGHT.
I already knew that her mother had died in childbirth with Elizabeth, and that she was brought up by her aunt, Margaret SOUTAR nee WIGHT, and went by the surname SOUTAR as a result.
However, I'd never figured out what happened to her after her marriage to David McLaren PAUL, so thought it time to have another look around.
I still cannot, as yet, find Elizabeth's death, but have now found David's, which was a bit of a surprise.
The informant for his death (in Glasgow) being his "sister-in-law" Helen E L BROWN of Edinburgh. This was the same Helen who was witness to David's marriage to Elizaabeth WHITSON or SOUTAR, her sister by adoption. Which all seemed fit and proper, and understandable enough.
Then I further investigated the scribble for David's wives and realised that the second, which I'd skipped over on first reading, was an Ivy Elsie POVOAS or SOUTAR.
Way too much of a coincidence that Ivy Elsie was a POVOAS, as Helen E L BROWN nee SOUTARs brother Charles William SOUTAR had married a Helen POVOAS, or so his death notice in the Scotsman had told me.
I'd never found hide nor hair of the existence of a Helen POVOAS, anywhere, although there was at least one family of them in Hackney, but no Helen.
Spurred on by this, and the more general availability of records on the internet these days, I have now found Charles' marriage to Ivy Elsie POVOAS (Manchester, 1927).
So Helen BROWN nee SOUTAR was sister-in-law twice over.
Interested to note that David McLaren PAUL's occupation of technical chemist (as per his 1916 marriage cert.) was translated somewhat more fully in the now available 1911 census.
It gives him as a technical chemist, but adds he was a worker for "explosives manufact."