Alexander West, 9, had gone outside to play when he left the backdoor open. The fox then entered and settled upstairs in the youngster's room.
His mother Dina Luminati-West told The Mirror: "Alexander shouted down saying there was a fox in his bed, but I didn't believe him.
"I thought it must be our cat asleep on his bed, but then I saw the long pointed nose and realised it was indeed a fox."
Luminati-West called the RSPCA who returned the fox back into the wild.
She added: "Alexander loves animals, but a bedroom's not the best place for a fox. We'll be keeping our door firmly shut from now on."
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