Have you ever had your children cross it?
My DD is going through some issues at her dad house right now and I think part of it may be her mothering of her half-sisters. DD1 does the same thing when she is home. (My kids are 18 and 21 and their sisters are 8 and 2). She finds being there very frustrating because she has very set views on what is right and what is wrong with taking care of kids (i.e. showering more than once a week, not giving them cookies before bed, bed times - things that she has had but her siblings have different), and I'm trying to remind her that they are her sisters and not her children.
The further issue (and this is really none of my business, but for advice purposes): when she is there or they are out for dinner she is the one who says 'no' or tells them to shower or go to bed or to stop hitting each other. No one ever stops her or says anything such as 'these are your sisters, not your kids. Please stop directing what they should/shouldn't do,' but they become irritated that she is acting more like a parent than a sister.
How do I get her to note her actions and step back?