if i were you i'd make it the new cool thing to take baths in the morning 
the boundaries issue is honestly not as big a deal IMO as the possibility that the parents will take it as a suggestion that they're neglectful and get angry or offended.
i know someone whose kids are always, well, grody. just like you're describing. it's honestly a bit of a red flag to me--even tho she obviously loves her kids, it's like some people just never got the memo on things like personal hygiene
i don't have a clue about what to do about it either 

the boundaries issue is honestly not as big a deal IMO as the possibility that the parents will take it as a suggestion that they're neglectful and get angry or offended.
i know someone whose kids are always, well, grody. just like you're describing. it's honestly a bit of a red flag to me--even tho she obviously loves her kids, it's like some people just never got the memo on things like personal hygiene
i don't have a clue about what to do about it either 






) and we were VERY uncomfortable that a provider decided to do that without asking us first. If i would have been approached about it first and told 'oh my routine is to give the children a bath in the afternoon' I would have still said no, but then I wouldn't have felt like something hinky was going on. I wouldn't think that it would be too much of an issue in your situation though b/c it sounds like you can let them know that they got dirty and give them a bath.

- but if I had one then (s)he should ask first. The issue is the level of supervision during bath time - I would want to be clear with the nanny about what my expectations are. I am not sure how it would work with 4 kids, since not all 4 would be in the tub at the same time.
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