So he is living at home
My guess is that he has been left an annuity in a will to fund his life.
I can only quote from a will of one my 4 x ggmothers from 1844
The trustees and executors were charged to apply the dividends and annual proceeds (from Grand Junction Canal Company shares) in or towards he maintenance of the three (yes 3) imbecile children of my late daughter.
One of these three died of fits, so I think that having epilepsy may lead to be classified as an imbecile.
However, having had a dig on the web I also found this
"I have just received the April edition of the Family Tree magazine which has part 2 of an article about hospitals for the mentally ill. It gives the following definitions in use until the beginning of the 20thC:
imbecile - 'mental age of an infant'
idiot - 'natural fool from birth'
lunatic - 'sometimes of good and sound memory and understanding, and sometimes not'
It goes on to say that the Mental Deficiency Act of 1913 introduced revised definitions:
idiot - 'unable to guard themselves against physical danger'
imbecile - 'incapable of managing themselves or their affairs'
feeble minded - 'needing care or control for the protection of themselves or others'
moral defective - those possessed of 'vicious or criminal propensities' "
