Unfortunately, my mother does not know much about her history, she originally gave me her mothers maiden name incorrectly, however, that being resolved, she mentioned seeing a picture on her mothers wall when she was very young. The picture showed a young chap in naval attire, and when prompted by my mother as to who it was, she was told that it was my grandmothers brother William who drowned at sea. I know no more than that.
I searched out the WW1 death index and found a William John Stainer of the Royal Engineers. ranked as a sapper, Number 508484. He sadly died in 1917 Vol E2 Page 42. The name fits exactly, but...
It seems inconceivable that a member of the R.E. would be dressed in naval garb for a picture, but, another further record reveals a William G. Stainer being in the Royal Navy as a paymaster, but dying in the explosion that destroyed the H.M.S. Bulwark, November 1914 on the River Medway.
If either record relates to my grandmothers brother, where do I go now to confirm, or, if it is a civilian drowning, out of wartime, where would that record be found

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Sorry it is a bit garbled, but there isn't an easier way to explain it all
