Answer / Explanation:
Referring back to the narrative of the question, it was stated that Gregory finds school stressful and it is worthy of note that stress when in excess can lead to a mental disorder.
Another reason the the fact that he has no relationship with his father but has with his mother and grandmother. This will at a point make him tend to think that he is more suitable as a lady or woman and which might have a draining effect on his thinking nature and in the long run might lead to depression and then to a mental disorder.
