....the family group that Annette has identified looks promising for John George
The only anomaly left now really is the difference in father's name on John's marriage certificate.
Just in case the Whites and Lawrences were once neighbours!

1907 Acton directory has
Colville Road
From Bollo lane to Stirling rd.Lawrence William (Windham villa)
White Edmd. (Orchard cottage)
Edmund appears as Edward White on the electorals around that time, landing at Orchard Cottage in 1907 from 27 Stirling Road.
William Lawrence on them at Windham in 1908, probably only time.
Windham Villa sounds grand, and I suppose it might have been, but it had a platelayer and his family living there on the last census, next door to the Whites.
If so, his parents were Edmund Joseph White and Clara Elizabeth Coombs although I can find no marriage between them.
Could Edmund have already been married to someone else?

Not sure!