I had problems the first couple of times I tried tampons, but I figured it out (as most kids should maybe?) and aquatic social situations went unhindered.
My dd hit the age where such discussions are prevalent. I'm 29, she's 9, and she has pubic hair, underarm hair, and training bras. I ALWAYS make it a fun and pleasant conversation, put the emphasis on her growth & developmental milestones (which is where she feels comfortable) and assure her I am here for any of her questions. I have NEVER heard of a mother placing the tampon physically for her daughter, and I consider myself an outgoing, educational mother. My former partner and I always gave dd privacy when she would "explore" her body as a toddler, and simply stressed personal space and privacy. I feel this is the same thing and let her know I'm here for her, but I would never infringe on her body.
As an aside, several moms have been correct in pointing out their own or their dd's concerns over cleanliness and discomfort with menstrual fluids,smells, etc. Tampons can hide what may embarrass or inconvenience an active young woman or girl. There is no harm in hiding your flow, but it should not be enforced to the girl's discomfort.
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