It's true, sometimes it may be dangerous.
When I was a child, I was only 8 or 9 in that time, one day I hit upon an idea to start a diary so I found a thin copybook without cover and with only a half of sheets but then my love for details apperared and I decided to write down EVERYTHING what I did that day, including cartoons watched by me and what I ate for breakfast but I realized it's impossible to write with so many details so I put the diary to the cabinet in my room, resigning from writing. After some time when I had already forgotten about it, my mother found it and despite my protests she grabbed the diary and read. There wasn't anything that could compromite me, she could read my school composition as well (apart from the fact that I always truly hated when somebody not being my teacher read my homeworks) but I felt humiliated.