A responsible parent takes the advice of a medical professional.
If you go back to the original post, the OP was clearly looking for a GP appointment but was disappointed it was a nurse for some reason.
The nurse has looked at said rash and assessed it is nappy rash. It may not be but until the OP follows the advice given, we won’t know.
The OP clearly came back from that appointment annoyed that they’ve been told it’s hygiene, came on here and now posters are saying it could be worms, could be fungal.
Well if you back to the original post, it states that the rash goes away and then it comes back. These things don’t clear without proper treatment, so it can’t be any of these. But the OP is entertaining these because it means that it isn’t a hygiene issue. Now armed with the advice of well meaning posters, the OP got the doctors appointment she originally wanted because now she will be stating she thinks it’s X,Y,Z.
At no point has the OP said that she has followed the nurses advice which I suspect was only given a few days ago. The OP hasn’t said I’ve been using wipes for two weeks, given a nightly bath, used a proper barrier cream (not sudocreme)…..but it’s not working.
This is a 9 year old who needs to have a degree of privacy too, yet will be back to the doctors again on Monday, missing school, because OP doesn’t agree with the Nurses advice but believes it could be something someone said on Mumsnet?????