Have you found a death for Harry Mady senior ?
I was searching for him too, and found the following:
In the 1891 census,
Frank Harry Sr is shown with his wife Minnie, and infant son Henry James.
This is for St. Pancras, sub district Somers Town, enumeration district 10.
Frank says he is 22, born Doncaster, Yorks, and is a book binder.
One and a half years later, Dec 1892, there is a
Frank Harry Mady, who says he is 19 1/2 years old, a bookbinder, born Doncaster, Yorks, living in St Pancras,
He states he has, for the prior 12 months, been living at 114 Euston Road, St Pancras, which is sub-district Somers Town, enumeration district 11. (RG12, piece 127 , folio 172, page 26).
His employer is Bookbinding Co. on Salisbury Street, London
He also says not married, and no children....
Either
Frank Harry has a younger cousin in the same profession, living very close by... or he left his wife?
There is no further help on the army documents... no discharge papers, nor NOK. The page for service info is blank. It is like he signed up, was listed as fit, then.... nothing.
*poof* He vanishes.

Edited for totally mixing up names! So glad Brigidmac picked up on it!!