This is a tough age for getting kids to wipe well. they either wipe too hard or not well enogh. In either case, the outside can get a little irritated. It does not sound like she has a yeast infection or urinary tract infection.
The baking soda bath is very helpful. I would also try some diaper cream to coat the surface and provide a soothing barrier.
In terms of preventing this from recurring, sometimes it is helpful to buy the flushing wipes for the kids to wipe themselves. there are different brands like kadoo, etc.
this will not irritate the skin like the toilet paper can.
If the rash does not improve in a few days, or if the burning worsens, she should see the pediatrician to make sure that she does not have an infection in the urine, a yeast infection or sometimes kids can get a strep infection in the vaginal/rectal area that requires antibiotics.
If she develops fever at any time, she should also be seen.
If you have any further questions, please ask.
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