When my sister was three years old, she cut her hair. On three separate occasions. Each time, she denied having done it, despite large chunks missing from her fringe, and lots of short hair in her bed. Needless to say, she was in a lot of trouble (increasing levels with each subsequent episode of hair mutilation). We thought she had finally learnt her lesson after the third go.
But no. 10 years down the line, and she cuts her own hair again. Not just a bit of a trim (which can be down accurately to one's own hair, especially a fringe tidy), oh no, my sister has to go the whole hog and attempt to cut in a new fringe. That's right, my thirteen year old sister thought she could restyle her own hair in the bathroom with a pair of nail scissors.
Unsurprisingly, it looked terrible, the mothership went spare, and my sister had an emergency hair appointment the very next day to have it rectified.
She did have to endure a day at school looking like a plonker though - maybe this will finally drive home the lesson 'Do not cut your own hair if you have not done a three year hair-dressing diploma'.
Sadly, I don't have high hopes for her ever learning this fact.