C.P.
B.,
Hi I am in a hurry so this will be quick.
I just wanted to say that my sis and I have a relationship where we take eachothers kids to the potty etc... My guess is that your sister hasn't thought about the fact that you have a lot to do - b/c you keep taking your neice to the potty and you keep doing things for her etc....My suggestion is just to say no. When it is suggested that you do it or your neice asks you, tell her to find her mommy - b/c you are busy, only do it isf you really do have the time. Tell them you just got a chance to sit down for a minute and that she can wait or find her mommy.
Does that make sense? Then it won't even be a "thing" and eventually I would think they would stop asking you.
NOW go put your feet up! : )