Answer:
A theory - a hypothesis.
Explanation:
A theory is an explanation for a certain phenomenon, supported by evidence and well substantiated, verified factors. Whereas a hypothesis is an explanation of an observable phenomenon, a prediction to explain a certain causal correlation of events. In this case, the theory would be that "misery loves company", and the hypothesis would be the observable event of several individuals who have received a bad news who then sought out for other people.