Hi. Thanks for your query. Noted the history bumps in between butt crack, of the size of boils but are not like boils as they pop up like water blister, don t come to a head, soft on top, get them on stomach also, leave a scar on healing and your daughter also gets similar ones. Sometimes leave dryness which bleeds on peeling. This is a rare form of dermatitis and can be diagnosed by the help of clear photographs or when seen actually by a Dermatologist. Hence I would suggest you the following: Consult a Dermatologist for clinical evaluation, examination, biopsy if needed to have a confirmed diagnosis. Once diagnosed the treatment can be well planed and be specific.