Sibling Stuff

They adore each other. They are each other's best buddy.
They have this pattern, though, in which I am a reluctant participant. 

She goads him, teases him, blames him for something he did or didn't do.
He pokes her and giggles.
I fuss. Something like, "No blaming, no tattling. Use your words, not your hands." 
She screams and slaps him and then giggles.
I'll raise my voice, "Stop rough-housing before someone gets hurt!"
He swears it's not his fault. She swears it is. 
He escalates and punches her.
She screams. Etc. (Extra.)

I had a migraine all day and had forgotten my meds at my house. So I had to drive the tank Suburban over to my place (about half an hour when the traffic isn't bad). While there we went for ice cream. Then I drove the tank Suburban back to their place, by then in Friday afternoon rush hour traffic. With them giggling and punching, tickling and poking, yelling and laughing, scheming and whispering, in the back seat. 

LIfe in the fast lane.