The best guess, Mary, is that another little girl at school or in the neighborhood has short hair she admired and that got a lot of attention. Or some child—possibly out of jealousy—might have said, “Your hair is ugly.” It’s also possible that it got in her way at play or work. Still another possibility is that she is very tender-headed and that the daily brushing or combing was traumatic for her. I have a little granddaughter with unbelievably thick hair. In her case, she never wanted it cut even one inch—but she never wanted it brushed either. My daughter-in-law is a very wise woman, and she handled it by simply brushing the top layer. The underneath layer would be a mess of tangles, but nobody ever saw them! Once a week or so she would work on that bottom layer and get out the tangles.
One other suggestion I would offer is a very simple but effective one: ask her. Wait until the dust has settled about the cutting episode, until both of you are calm and reasonably accepting of the situation, and say as you tuck her into bed one night, “Tell me why you really cut off your hair. I’m just curious.” If she says she doesn’t know, suggest that she think about it and tell you later. She may later give you an answer when you’re not even thinking about the question, making you struggle to know what she’s talking about. But, in time, she will probably tell you.
Finally, keep in mind how fast it will grow back, and don’t let it fret you. The hair of a child is a wonderfully renewable resource.
Our parenting advice is given as suggestions only. We recommend you also consult your healthcare provider, and urge you to contact them immediately if your question is urgent or about a medical condition.