Get exederm cream and bodywash.I no theirs a avino oatmeal bath and cream its thick but its way better then sunblock just my opinion
I have an allergy to a common sunscreen additive called PABA - I break out in hives if I use sunscreen that contains it. There are PABA-free sunscreens, the one I always used growing up is called NO-AD and it has always worked for me. Maybe you could try that - it might be a contributing factor to the rash.
Huggies has a good kind but u have to order it. I buy the banana boat kind that says "naturals" on the front. One of my girls breaks out otherwise (dont get spray ons they are the worst)