This family is quite easy to trace through English Census returns and
www.freebmd.org.uk website. George was clerk/warehouseman for steel company in London before he enlisted (so did some of his cousins). Father William & mother Annie (nee Kebbel) lived 31 Matilda St, Bethnel Green most of their lives. Bill, some brothers & father Frederick were all boot/shoemakers.
From
www.freebmd.org.uk website you can note index data for marriages or births, etc and then go to
www.gro.gov.uk and order copies of certificates. They take about 2 weeks. I have used credit card with no problems and cost is about 7 pounds. Fred Gladden b.circa 1823, married Emma Bates, registered at Bethnal Green 1844.
I hope you won't mind if I query George's death at Gallipoli 15 Sept 1915. Is it possible this is another George Gladden?
I think your George was George Henry Gladden b.1891.
There is record of a George Henry Gladden, private with Royal Welsh Fusiliers who enlisted Dec 1915, served in France and "disc. 16.11.1917".