Sisterly love, in different shapes.

The era of arguing siblings has entered the house of Payne, and now I understand the frustration of my mum and all the other parents who tore their hair out in despair when war broke out at home. It really is heartbreaking, and so difficult to deal with. To be honest I'm a little surprised by it, because there is a bit of an age difference between the girls, but when the littlest one is as fierce and decisive and temperamental as ours, conflicts are bound to happen. She knows what she wants, and her big sister doesn't want her toes stepped on either (or her hair pulled, or getting whacked on the head with a hard object). Yes, there has been violence. And screaming. And crying.
So the question is; what to do? I've read that parents preferably should stay out of the conflict and let them sort it out themselves, and sometimes I've seen that it works. But sometimes my instincts just kick in, and I have to do something, interfere, explain, comfort, try to guide them, or separate them at worst.
I know I shouldn't worry, that it will pass, it's all in phases, that it's a natural part of their development. But it's still difficult, and strange, and frustrating. It even is a little bit fascinating, because suddenly, in a fight, as if someone swung a magic wand over their heads, they are the best of friends again, kiss, hug, make up, and it's all forgotten. Weirdos!