What is this?

Mo

My little guy, almost 2 has broken out in this rash! We’ve not changed anything but are trying an all natural soap now instead of what we had. That isn’t helping either. Mixed some 1% OTC hydrocortisone cream in with his usual lotion (aveeno repair) which seems to have calmed it down. I don’t want to be that mom who take her kid in for a rash that’s easily fixed 🤦🏼‍♀️ I may just have to. What you see here is on both arms and he keeps pointing at it saying “hurt!”. Ideas?