回复：我女儿也有相同症状

I agree with you. From the location and symptoms she described, it sounds like atopic dermatitis (eczema). Use detergent/cleansing agent for sensitive skin, heavy moisturizer several times a day (right after bathing, pat dry), if still not better, over the counter 1% hydrocortisone is ok to use occasionally, depends on the severity of symptoms.