Math quiz time between siblings

I am driving in the car with my nearly 9 year old 3rd grader and my nearly 2 year old toddler. K-A has decided that she is going to quiz E-G on her math lessons. Mental math, ya'll.
***
K-A: Ok, what is 7 + 2?
E-G: NINE!
K-A: Ok, what is 5 + 4?
E-G: NINE!
K-A: Good job!
E-G:
K-A: Ok, what is 4 + 4?
E-G: NINE!
K-A: No, E-G that's not correct!
E-G: NINE!
K-A: No. Let's try another one. What is 2 + 2?

E-G looks at K-A and promptly punches her in the face.
***
On the one hand, (sigh) "Don't hit your sister..."

On the other hand, I'm kind of impressed by the way a 2 year old is so casually willing to visit violence to keep her big sister off her back.