Eyes in the back

One afternoon, Anna was driving with her two little kids, Zoe and Zack, who were in the backseat. After a few minutes of listening to them argue, Anna yelled,

“Knock it off, both of you!”

Zoe, the eldest, asked,

“How do you know what we are doing at the back mom?”
“Mummies have eyes in the back of their heads,” Anna replied.

A few months later, the kids were again out driving, while doing some errands.

“Mummy,” Zack asked innocently, “do you still have eyes in the back of your head?”
“Of course I do son,” Anna responded “Why do you ask?”
“Well,” he said, pointing to the object in his hand.
“I thought maybe you could read us this story book while you drive.”

Anna, dumbstruck, drove on…