I have now received my letter from the HH. Posted 7 Aug, but delayed because it went to the address on electoral register of 2002. We moved in 2003 and opted for closed register as soon as it was possible.
As well as the spurious 3 children even my brother noticed, he has not included the cousin who I understand has signed up (He was born abroad as his father was in RAF at the time). He must have sent letter to his mother (my aunt) who died a few months ago and he got it because he was her executor.
He has missed out another first cousin - can't see why as mmn is correctly transcribed on freebmd.
He has marriage of one of my father's uncles correctly, but didn't spot she was a widow when she married, so has failed to find their children, as they would be indexed with her actual maiden name, not her first married name.
Another of my father's uncles is married correctly but again none of his four children listed - they are also easy to find, especially as their descendants are still living within a mile or two of where my great grandparents are buried.
It's even worse than some ancestry trees!
I think I have tracked down a living relative of the actual deceased lady, grandson of her mother's half sister - don't know if they can inherit if only half blood.