I thought I had, and had duly written up all the stuff for granddad and great-granddad. (There are still a couple of items to continue checking - mainly newspapers because granddad often won angling competitions - but I've noted them.)

I've just had an offer to takeout a Diamond subscription to 'The Genealogist' for fifty quid less than normal. I hadn't checked out all the items they have that differ to FMP and Ancestry but I thought it worth a punt.

So, to try out how good their search engine is, typed in granddad's name and birth county.
'Oh, there he is.'
Hang on, that says birth 1895. Granddad was born 1900.
Scuttles off to check GRO historical births index.
Correct mother's maiden name, so obviously that Thomas died before 1900 when granddad was born.

Um, there's no death registration. Checked FreeBMD, FMP, and the GRO historical deaths. Searched with first name and surname. Searched first name only. Searched last name only. Found four baby deaths for that surname in the correct registration district between 1895 and 1901.
Which of course lead me to check for births for those children. In addition to Thomas, two others matched my great-grandmother's maiden name.

Still can't find a Thomas death registration, but there's a Charles who's the right age and they called a later child Charles, so I think Charles is actually Thomas.

I had to think how I'd missed all the extra births, eventually remembering that great-granny died in 1905, so she isn't on the 1911 census, and obviously there are no marriage/children details beside great-granddad who is a widower (and living away from his surviving children).

So my check-list of 'things to do' now includes a column which says 'check the GRO Historical births and deaths indexes'.

I should add that I had gone through the pages of baptism registers for three local churches looking for granddad and his sister without success, though as two of the 'new births' are prior to that of the sister I might have to do a little extra searching.

The other 'success' is that after paying for three birth and three death PDF certificates I still have eight quid left from my 'save fifty pounds' offer.