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Enter Surname as Hailey; enter Mother's Maiden Surname as "Stannett".
Enter years as 1920 through 1950.
There are 4 births in Watford (1924, 1929, 1937 and 1941).
Also 2 births in Eton (1920, 1925) and 3 in Berkhampstead (1932, 1934 and 1935).
So it looks like more than 1 marriage of a Hailey to a Stannett

Ethel Emily married Charles Hailey in Eton, 1920.
I can't name any of the children as they may still be alive - and that would be against RootsChat rules.