Was Gladys a twin ?
Births Dec 1918 (98%)
Ford Dorothy L Garwood Hendon 3a 479
Ford Gladys E Garwood Hendon 3a 479
This is the only marriage I could find
Marriages Dec 1915 (>99%)
Ford John F Garwood Bristol 6a 596
Garwood May F Ford Bristol 6a 596
If you buy the marriage certificate it might give you more clues
www.gro.gov.uk they cost £9.25
Possible birth
Births Jun 1894 (>99%)
Garwood May Florence Epping 4a 352
Garwood May Florence Islington 1b 327
John Fran Ford is a bit harder to find because there are so many