Answer:
loneliness
Explanation:
Loneliness is a feeling or a mental emotion that people often feels when they are alone. It is a quality of being left alone and people feel sadness when they are separated from their family or when some loved ones departs.
Thus in the context, the Klumps whose children are married and have stared their own family, and the other child had just moved to the city where he have his own apartment, Klumps will now be alone and sad because they are now left alone in their house and their children have moved away. They will experience loneliness.
