If the character of Herman is examined, the narrator's brother, it is clear that his character is developed in a number of ways. Firstly, characterisation occurs through the way he speaks and how that speech is described. Note that when his brother wakes him, Herman responds in the following way:
"Awp" he said in the low, hopeless tone of a despondent beagle...
This a rather humorous and funny comparison to make, as the narrator describes his brother to be a "despondent beagle" rather than a human, and the sound he makes shows that Herman is very afraid and fearful. This is supported by the next method of characterisation, which is the background information given to us by the narrator himself, who reveals, "he always had suspected that something would 'get him' in the night." This, combined with the way that he is described as being rather "green" when his mother sees them clearly supports his characterisation as a young boy who is full of fear and terror at the supposed "ghosts" who are lurking downstairs.