I have a theory, albeit farfetched and slightly paranoid, that I think many mothers would agree with. I believe that when your first child is born, you leave the hospital, or your birthing bed, not just with your precious newborn, but also, with an ass sensor.
Perhaps there is a dormant part of the female anatomy that is activated by all that pushing, or our doctors and midwives install it unbeknownst to us while cleaning us up down there.
But both of these theories go out the window when I consider adoptive mothers, as well as fathers, who clearly have one too. And so, the most plausible explanation I've been able to come up with is that it has something to do with hormones.
The ass sensor makes it near impossible to sit down for any length of time. I believe it works on some frequency that only dogs and children can hear, and the closer your posterior gets to a seated position, the louder it gets, until your children can no longer bear its horrible high pitched sound, forcing them to use their wits to quickly come up with some minor calamity that needs rectifying immediately.
The timing is so impeccable that is is the only explanation I can come up with for why, once I have cooked, served and cleaned up breakfast, and prepare to sit down for a cup of coffee and to glance at the paper, someone appears with a nasty soiled diaper so disgusting that it needs to be changed right away. My children have heard the lure of the ass sensor.
Or, when I sit down in my study to write, before I have composed a complete sentence, I am summoned to break up a squabble. Because from far across the house, they were possessed by a sound not unlike nails on a chalkboard, and they needed to do something, ANYTHING, TO MAKE IT STOP.
The acoustics of the toilet must do something to amplify the painful effects of the ass sensor, because the last time I relieved my self in peace was sometime in early 1999.
You can try to ignore your children when the ass sensor sounds, but it's ear-splitting kilohertz frequency is so painful for them to endure that it only works up to a certain point.
Once, a friend and I devised an experiment. We were in my kitchen on a Friday afternoon, and all our children were happily playing in the backyard. We sat down to enjoy a drink, and gab for a bit, but the combined power of two maternal asses hitting chairs was clearly too much for the kids to bear. Because my iPhone has a stopwatch, we decided it would be fun to time how long we could sit before the ass sensor sounded.
The record: 36 seconds.