The same type of rash has recurred twice in two weeks. What could it be?

Hello doctor,

There is a red pimple-like rash or hives on the chest up to the jaw line on a four year old female. It turns white when pressed. It always appears after a court-ordered visitation. The only factors we know of are stress or anxiety from not wanting to go, both of those conditions were confirmed by a therapist and diet since he always feeds her pizza or another pre-packaged and processed food. What could it be and how should it be addressed? Her pediatrician says it looks like a viral rash but is concerned about the timing of the occurrences.

Hello doctor,

Thank you for the reply. One of the spots opened up tonight after a shower. You can see it in the pictures.

Thank you doctor,

It is day-2 now. It was present when she came home last night. We have not noticed her scratching or rubbing it. She seems to not even know it is there. We have tried several different creams, such as antibacterial, antihistamines, baby powder, eczema cream, and tonight I tried two different antifungal creams in two different areas to see if they have any effect. So far, nothing seems to lessen or worsen the bumps. She was checked for a strep infection a few weeks ago, but the results were negative. She did test positive for type-A influenza at that time and was prescribed Tamiflu. Her last dose was over two weeks ago. Regarding family history of psoriasis, there is none that we are aware of. The rash is only present on her chest from one armpit to another and from the bottom of her rib cage up to her cheeks. The onset is very sudden. She left yesterday morning with nothing and came home with the rash. Two weeks ago, it was the same situation. She left on a Saturday morning free of rash and came home on a Sunday night with the same kind of rash she has now. We are not sure of the environment she is staying in and all we know of her diet for these visits is that it is processed foods and lots of starch and carbs. Once it appears it does not seem to worsen. It takes a minimum of three to four days to get it under control and then disappear. The same goes for the first time we saw this. After around a week, it was gone. Then she had her visitation and it was back again. Tonight was the first time we observed any of the bumps bursting open. She is 4 though. So, she could have scratched it. We are continuing to monitor her for more of those.