When Do You Stop Bathing Kids?

Obviously, your kids should always have good hygiene, but when are they too old for you or your babysitter to help them out? Think of an age. Do you have it in your head? Was it 13 years old? I kinda doubt it. But a boy that age was being bathed by his sitter. I don't think there was anything inappropriate happening, but it seems a little old to me.
Here's the question posted ON TOPIX:
My husband and I have this very nice lady stay with our two boys when go out of town. We've been using her for most of my older son's life, and we all love her to death. But I just recently realized that she has still been giving both our sons (age 5 and 13) baths together. She'd tell me on the phone that she had given them both baths, but I didn't realize that she was still shampooing the older boys hair and drying him off etc. along with the younger one. Sure I knew she was bathing them together years ago (back then I did it that way too), but I just assumed that this had stopped at some point (in regards to the older boy) years ago.
-NewsAnchorMom Jen
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