Guestx2,
Surely if you PM the above 3 relatives at least one of them should be able to answer your question.

BTW there are 2 of HC's sheet music pieces on Ebay currently. One very scarce one 'Robinson Crusoe' is already going beyond my pocket at £16 plus postage, but the other 'Paddle Your Own Canoe' is quite common. I have 3 versions of it all with different lithographs to the one on Ebay. This in itself would make an interesting study. In all my copies his face is much fatter. I would love to see a website of his work something like the one dedicated to Arthur Lloyd.