I will not have Mr Jackson he never wipes his feet

Mrs. Tittlemouse decided to leave the bees till after dinner.
When she got back to the parlour, she heard some one coughing in a fat voice; and there sat Mr. Jackson himself!
He was sitting all over a small rocking-chair, twiddling his thumbs and smiling, with his feet on the fender.
He lived in a drain below the hedge, in a very dirty wet ditch.

My son went into the parlour to fetch something and exclaimed 'There's a toad in here!' Well I know the house is damp but...
There is no direct access to the room from the outside.
Cats don't mess with toads - their skin tastes bitter.
How long has this toad been residing with us?
Mr Jackson is out of doors now but the mystery remains.