The answer words in the flat below differ by a single additional letter. The shorter word (first set of blanks) is capitalized.

The donkey was gloomy,
Unpleasant to look at.
Grey, stuffed and depressive,
_ _ _ _ _ _  was rather an _ _ _ _ _ _ _ .

(BIG) HINT:  
Winnie the Pooh

Answers:

EEYORE was rather an EYESORE. 

Credit:
The Enigma
NPL Magazine
November, 2019
WITZ