I came across a line when reading Alice Munro's stories:
Another possible reason for his growling dislike has just occurred to me, and it’s odd that I didn’t think of it before. We were both flawed, obvious victims of physical misfortune. You would think such people would make common cause, but it could just as often happen that they don’t. Each may be reminded by the other of something sooner forgotten.
It appears to me the last sentence means:
Each may be reminded by the other of something that would soon be forgotten/we'd soon forget.
A different sentence with soon would make sense to me, not the sentence as written. But what does "sooner" mean here in this sentence? Sooner than what?