I did not see the push up bras or thongs

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I just saw the frilly pink body suit things and the tutu. They seemed ok to me.
I'm a bit more relaxed about things like makeup though. My 3 year old likes it cause she loves to paint on her face and body and look like her daddy. I see that as harmless, on par with helping me lay bricks.
I think teens should be free to express their sexuality as long as they do it in a safe way. They do become very much sexually capable beings after puberty, The whole physically capable but not mentally responsible is the main issue I think. If my daughter at 12 wanted to dress slutty they can go for it, they just won't be going out looking like that.
I agree though, kids should be able to enjoy being kid. I think you need to be clear about the division between play vs actually wanting to look 'sexually attractive' at a young age. The former is ok, the later not so much. For my daughter makeup is just play.
edits: oops, I'm not sure I'm quite sounding right here....I think I have it now. I don't want to sound dodge. I'm not in any way condoning the sexualisation of chilldren.