As you say Ernest J Crabb married Laura N M Nightingale - registered in West Ham 3rd quarter 1919.
There is a birth registration for Ernest John Crabb also in West Ham 2nd quarter 1895 which may well be the one you are looking for.
Let me know if I can be of any further help via email at firstname.lastname@example.org
John Crabbe. (Member 629, Guild of One-Name Studies, since 1984.)
Researching Crabbe/Crabb/Crab/Craib & allied families worldwide.
Website "Crabbe Family Pages" at - http://crabbe.info/
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