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My 20mo grabs at her genitals whenever she's naked (which is often as it's warm outside and she's toilet learning). She yanks on the outer labia and pokes at the inside. It looks rough to me, though she doesn't seem to care. I keep her nails trimmed so she doesn't scratch herself. I'm hesitant to stop her because I don't want her to feel shame for being curious about and exploring her body.
What's an appropriate reaction to this? I want to teach her it's ok to touch her own body, but she should be gentle so she doesn't hurt herself (Is she cognitively able to understand that if it hurts she has to stop? Can she make this connection?)and there are appropriate times and places to do this. What language should I use?