In fact, you know what, OP?
Go run a school. Just try it, for a term. Manage the ridiculously tight budget; hit the insanely over-inflated targets; make sure you don't miss a beat in terms of child protection, of course; look after the staff, and ensure they are all motivated whilst implementing an inforced performance pay related scheme; and all the while keep up positive, proactive communication with the parents who have entrusted their children to your care.
Introduce a programme of outside learning, and make sure no child is excluded from it. Ensure they all Make Progress, according to limited, but rigid, criteria.
Don't forget breakfast club. And homework club.
Constant, constant CPD, of course.
And then, OP, let's see how important this "power mum" is to you. How much she influences you. What priority you give her kids.
Let's see how much time you have for petty politics.
I think you might be surprised.
That parent who is getting your knickers in a twist? She only matters to you.