A Strange Observation

I have noticed something odd about Rebecca. Whenever I need her to hold still for something -- changing her diaper, dressing her, etc -- she wriggles around like a maniac, screams, cries, rolls over, tries to throw herself off her changing table... it gets to the point where I am afraid she will do herself bodily harm in her struggles. This is not the something odd. What's odd is that when I bring out the fingernail clippers -- and I mean every single time, without fail -- she holds perfectly still and lets me clip her fingernails to my heart's content. Even if she was struggling madly during a diaper change an instant before.

I am trying not to read too much into this.