They're all towers. But the buttons are all pretty shallow with very light actuation force required.

And they all happen to be situated such that the corner which has the button is the corner furthest away from the desk, so when she jumps up onto the PC as a platform to get ready to jump onto the desk, her feet are all grouped up right in that corner.

And you can imagine that if she's crouched down ready to jump, and I put my arm out to prevent her from jumping from the tower to the desk, that's a lot of pressure all applied to her little toe beans.

It's an unfortunate coincidence. But that experience, together with seeing this Mac Mini design, has made me wonder why we tend to put a button with such drastic effects right out in the open like this.