Review the Footage
In the UK, my mum and dad had just rented a house. I live with my mum, dad, brother, and grandad. We have been going to school as usual, one day I had to go home early (due to covid-19).
As I was about to unlock the front door, I hear someone running up and down the stairs on the top floor (we have three floors btw).
I unlocked the door quietly, went into the living room, and closed the door. I set up a camera in my room a few months ago and only I have access to it.
I went on my phone and checked my camera. Luckily my bedroom door is open—what I saw scared the heck out of me.
On the camera I see my grandad walking up and down the stairs over and over again, he was smiling and it really scared me.
Then he stood in front of my bedroom door and continued to smile, he was just standing there. I was so scared I ran out of the house through the backdoor with my bike.
I quickly called my mum and dad about what I saw and they quickly come home. I showed them the footage, I found out a few days later that he has been taking drugs. Story credit: Reddit / Gacha-YMS