I was the first child. My mother was the youngest of her siblings and had never been around babies until my birth. To compensate, she read all the baby manuals she could find, and I started out life in as sterile environment as could be managed. Nursing bottles, pacifiers, baby blankie, diapers--everything was boiled to within an inch of its life and handled with care.

Not a speck of dirt was allowed in my crib, the floor was scrubbed every day, and I was bathed to within an inch of my life, to hear my mother tell it.

However, my mother worked at Pratt & Whitney, testing aircraft engines (this was WWII), so she had to return to work, leaving me in the care of an elderly gentleman who live upstairs from us. Needless to say, this man was not versed in the latest 20th century version of infant care.

One day my mother came home to pick me up and to her horror saw me drop my bit of melba toast on the floor, the old guy pick it up, blow off the dog hair, and hand it back to me. She said it was the most horrible thing, so unsterile!

But as I clearly was thriving, and he was doing me no harm, she relaxed about the whole thing, and gave up trying to bring me up in a clean bubble when I started to crawl.

During my childhood, I grew up on a farm, going barefoot, friends with cats and dogs and animals galore, playing in the soil (aka gardening) and generally was pretty relaxed about dirt, though my mother did insist on washing hands and face before eating, and don't rub my eyes with dirty hands.

Now there is a scientific study questioning why babies put everything into their mouths. It's instinctive, it seems: Not only does this allow for the ramp up of immune responses, which will be necessary for protection from disease, but it also plays a critical role in teaching the immature immune response what is possible to ignore.

I'm sympathetic to all the people around me wheezing and breaking out in rashes and coughing and very grateful for my solid immune system. Dirt, glorious dirt!