Hi Margaret
I'm concerned that you have your real name showing. If it is then I would urge you to change it as all posts can be seen not just in the forum but on the wider internet. You can learn how to change it here "My full name is showing - how do I change it"
benefitsandwork.co.uk/guides-for-claimants/faq/forum#two The point of ADP is to provide people with support for their disabilities. They can use the money awarded in any way they see fit, and your sister has chosen to use some of it to have a cleaner.
Your sister's enhanced rate will only change if 1) she informs them that her condition has improved (which it hasn't - so she won't be informing them of anything) or if at some point she has a review and the assessor decides her condition has improved. - (this is unknown and could happen to anyone at any time).
So your sister's current award is unaffected by her having a cleaner - and no, she doesn't need to inform them how she spends her award.
BIS