The most difficult thing about being a parent of a toddler is not knowing when the transformation will take place. My son could be complacent and cooperative for hours, lull me into a false sense of parental confidence, then suddenly transform into Mr. “I Do It Myself” while standing at the head of a long restroom line at a crowded restaurant.

I’m never sure which personality my son will have when he wakes up. Some days, it takes me three minutes to get his teeth brushed, hair combed, and clothes on (including shoes). Other times he greets me with the dreaded “Me do it!” and he emerges from his room 45 minutes later wearing shoes (usually his sister's) on the wrong feet, both arms and his head through one sleeve of his shirt, and a bedspread cape. This usually happens on days I need to be at a public place, early.

On some days, a ride in the car can be an educational treat. My son delights in pointing out the scenery on the side of the road.

“Look Mommy,” he says gleefully, “cars!”

On other days, I feel like I’m being held hostage by a car seat terrorist.

“Mommy, go! Mommy, stop! Mommy, that way!” he commands from the rear during a red light.

At lunch time, I either put a sandwich in front of him and he eats it, or he insists on making it himself by smearing peanut butter and jelly on two slices of bread with his fingers and using the cat as a napkin. Then he pours the milk over the side of the glass and turns his sandwich into a boat which floats off the edge of the table onto the floor.

I am reduced to taking him only to public places that have carts with working seat belts, loud music, or lots of other two-year olds. I always have enough money for a phone call in case the police arrest me on suspicion of kidnapping a screaming toddler, who prostrates himself in an aisle for two gallons of gum ball ice-cream, and screams the whole way to the car.

I used to worry that my son’s behavior was my fault. What if I’m too strict and he grows up rebelling into a 400 pound ice cream addict who never goes to bed and watches continuous cartoons while coloring on the furniture? What if I’m too lenient and he never grows out of throwing tantrums on the supermarket floor or insists on wearing his Batman costume to his wedding? Or worse, what if there’s a cure for his behavior and I’m the only parent who doesn’t know it?

When I was pregnant, I swore my children would never wear bathing suits to the store in the rain or eat candy before ten o’clock, but now I know the second year of motherhood is trench warfare and I’ve got to choose my battles.

Just when I’m wiping the sweat off my brow, ready to wave a white flag and abdicate my position of parental authority, my son nods and says “Yes Mommy,” then flashes me a stunning smile that makes all the “nos” of the day disappear. I sigh with relief as he is transformed back into a sweet, obedient child and I feel like the luckiest woman in the world to have a toddler -- until someone looks at him too long, or breathes his air, and he turns back into a little monster.