Mood congruence is a psychological phenomenon. It is related to our mood. In this phenomenon, the person's mood is consistent with the information that the person remembers.
Even people remember the information that is associated with their experience at a certain point in time. If a person is in a happy mood then recall happy memories but if you are sad then you will recall the bad memories. When you are learning and you are angry at that time you will remember less positive events.
Thus here in the above context, Scott is in the state of mood congruence because of his father's death. His father's death leads to the other sad memories along.
