This story happens often here at our house. The creepiest part is that it always happens while everyone is asleep. It first occurred while both my brother and father were alone in the house. They went to their own rooms to have their afternoon nap. They were awakened by three loud knocks on their doors. They both came rushing to open their doors and to ask if they need something. But to their surprise, neither one of them did it as they were asleep. When I came home they told me what happened. I am not a skeptic to the paranormal but I didn't believe them because what happened was new and we lived here for quite a long time. I didn't think about it after that.
One night while everyone was asleep, I was awakened by loud knocks on my door. I am a light sleeper so I am sure that I heard three loud knocks. I opened the door quickly thinking that someone needed me urgent. I was shocked to see no one there. I checked the time, it was 3:40am. I can't think of any reason why or who may knock at that time. In the morning, I remembered about what happened to my brother and father so I told them what I experienced and admitting that I believe them now.
This happened a lot of times after that. One night my brother was having a high fever so I decided to sleep in his room just in case something might happen to him. We were both asleep, then again I was awakened by three loud knocks on his door. I opened it furiously and ready to face whatever is doing that. And again, nothing was there. I searched the whole house to find nothing. I went back to the room and found my brother awake. He said that the knocks woke him.
These always happen when everyone is asleep. It is always three loud knocks on our doors and it only knocks in the room where someone is. I researched about this and there is a superstition behind it. Three knocks on doors means that someone in the family will die. Well so far no one has died.
Glad everyone in your family is safe, and thank you for sharing!