Ghosts, are they real or a figment of our imagination?

When I was a child, I would spend the summer over my grandparents house with my brother and two cousins. The house only had two bedrooms so I would sleep on the couch pressed tight against the living room wall next to the hall entrance while my brother and cousins slept a few feet away on the floor in their sleeping bags.

Every morning, after the grandfather clock chimed three times, the bathroom door inside the hall opened and the wood floor creaked as something heavy stepped into the hall. T...