When my kids had a really bad diaper rash, I would use shortening/cooking oil.
I would get a napkin and get a little bit of shorting/cooking oil and PAT it over the entire rash area.
It's better if you take your "Little One" a bath and make sure you dry the rash area, then apply the shorting/cooking oil, gently. Apply each time you change your "Little One's" diaper, until it's gone. Usually, by the next day it starts going away. Good Luck!!!
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