Your child might be having sensitive skin and Johnson baby soap might be proving a bit harsh on skin for the baby. If you are not gettting Dermadew soap, try finding cetaphil
bar or hydrate bar or you can try any soap free cleanser. Both of them are quite mild and might suit to your needs. Always do a patch test
with the soap rather than using completely on your child's skin i.e. wash a small area with soap and see if it suits to your child's skin. Take care.