I have just spotted your message 5 years after you posted it. Hopefully you are still keeping tabs on this message board.
I can inform you that Sidney was my Great Grandfather, in fact I had the honour of visiting his grave for the first time in Boulogne this summer.
I don't know much about what happened to his wife, but his daughter Doris was my Grandmother. She was born c1913 and died in 1997. She had 3 children, two sons and a daughter. Doris lived in London for most of her life, but did emigrate to Washington DC between 1967 and 1982. She returned in 1982 and lived in Southport near my father and then to St Albans near her other son.
This is a synopsis of her life, if you want more info please email me at firstname.lastname@example.org