J.W.
That isn't a sensory processing issue. I know because Genna doesn't have any sensory processing issues. My god! getting that girl to wear a bra was 20 levels of hell!!
We started working on it when she first started developing. Like the mosquito bite stage. We tried those stretchy training bras, she hated them. That little plastic thing drove her nuts! So finally I went with white sports bras. Those seemed to work though she still forgot to wear them every day.
Since then she has developed more and now prefers regular bras over the sports bras because the straps are smaller and don't peak out. The other thing is now that she has boobs, she doesn't forget! Thank god!!
This may not seem like much but this was a two year process which included peer pressure from her big sister she adores.
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Not saying she doesn't have sensory issues, god knows Andy has them. I was actually shocked that kid wears boxers. It is just Genna doesn't have any sensory issues but still hated the bras. We started when she was ten, she just turned 12, I would say she consistently wore them this year.
Oh fudgicles!! I just realized why she probably never forgot this year, sixth grade. She has to change into her gym clothes in an open locker room.....mystery solved. :)
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Looking at SweetChaos' answer, those were the bras were the same sports bras we found.