Suggest Remedy For Itchy Skin Around Anus

my daughter is 9 and has a very itchy bottom around the skin area rather than the anus, she has had this problem before and it take weeks to gee it to go away. it annoys her so much it wakes her up with tickling & a slight itch feeling I think it may be from citrus & stone fruit. I have stopped her from eating this for now. just wanted to know if she can have a bath with something in it or what cream you would recommend to stop the ticking/itching feeling, she does not itch it & its not really red just a slight darkish red. thanks andrea