Today, millions of mothers will open sentimental, hand-picked greeting cards from their children, lauding and thanking them for the myriad of things they do throughout the year.

Themes will include hugging, kissing, cleaning, cooking, car-pooling, consoling, teaching, mending, healing, cheering, not sleeping, cupcake baking, nose wiping, diaper changing, bathing, last-minute costume making, dog walking and providing a perfume-sceneted shoulder to cry on.

There’s no question that mothers are adept at all of those things. After all, that’s what we do.

But, what Hallmark never acknowledges is the one thing moms do best, better than anything or anyone else on the planet: worry ourselves sick.

The agony starts when the child is still in the womb and a mom-to-be pummels herself with angst-provoking questions: Am I eating enough? Will one glass of wine hurt? Is the baby kicking too much? Too little? The heartbeat sounds so fast; is that normal? Is she getting too big? What if he’s premature? Am I really ready to be a mother? I’m still a baby myself!

With delivery comes a whole new set of anxieties.

As the 1983 tear-jerker “Terms of Endearment” opens, Shirley MacLaine’s Aurora Greenway is an anxious young mother, checking on her newborn, Emma, every five minutes at night, imagining the worst. She stares at the infant sleeping peacefully in her crib and cries, “Rudyard, she’s not breathing!” With that, Aurora climbs over the guard rails and shakes Emma out of a sound sleep, causing the baby to bawl. “That’s better,” she says and leaves the room, satisfied.

I don’t know a single mom who didn’t see herself in that classic scene.

Young mothers are master worriers because, with each day, they realize there are 10 more things they don’t know.

They fret about breast milk versus formula, the various hues of poop (which, astonishingly, can cover most of the color wheel), bilirubin levels, shriveling umbilical cords, to circumcise or not circumcise? And, if so, when?

Is he sleeping too much? Too little? What does that halting, high-pitched cry mean — dirty diaper or colicky stomach? Why isn’t she scooting? Is he hitting all the developmental milestones on time? Am I doing enough? Am I doing enough? Am I doing enough …?

Believe me, if you see a newbie mom who appears confident and in control, she is either one heck of an actress or delusional from sleep deprivation.

Of course, it only gets worse before it gets better. (Check that, it never gets better.) As the child grows, the angst deepens while Mom futilely attempts to control the child’s environment, starting by turning her entire home into one giant padded cell.

Every morsel of food that goes in the child’s mouth must pass USDA-level inspection: Organic baby food or Gerbers? Soy or dairy? Are these farm fresh eggs from actual free-range chickens or were they collected 4 weeks ago from neurotic birds trapped in bacteria-infested pens?

The other day in the grocery store, I saw a young mother examining the label on a container of yogurt. She stood there reading so intently and for so long, she almost didn’t see her toddler preparing to dive-bomb out of the cart.

The teen and young adult years bring a whole new slew of worries.

Is my child popular enough? Is she TOO popular? How are his grades? Do they have enough extracurricular activities? Do they have too many? What if she goes out and someone puts a roofie in her drink? Who is that boy she’s talking to and, more importantly, who are his parents? Is that a hickey? Do they realize the AIDS epidemic is still alive and thriving in this country?

If they go out, you worry until they walk through the door. If they stay home, you wonder why.

Then, they grow up and move out of the nest. And boomerang back again, then out for good. Still, you worry about their job and marital status. Will they ever give you grandkids? Have they started a 401K?

For the rest of your life, you’re tortured by the question: “Have I mothered too much or too little?” And you realize you will never, ever know the answer.

So, you’d think the perfect Mother’s Day gift would be a day without worry. Twenty-four blissful hours without a single concern.

But, you’d be wrong. Moms wouldn’t know what to do with ourselves if we weren’t fretting about something. After all, that’s what we do.

— Cathy Hamilton is a 54-year-old empty nester, wife, mother and author. She can be reached at can be reached at 832-6319.