According to theories of gender constancy, until they’re about 6 or 7, children don’t realize that the sex they were born with is immutable. They believe that they have a choice: they can grow up to be either a mommy or a daddy. Some psychologists say that until permanency sets in kids embrace whatever stereotypes our culture presents, whether it’s piling on the most spangles or attacking one another with light sabers. What better way to assure that they’ll always remain themselves? If that’s the case, score one for Mooney. By not buying the Princess Pull-Ups, I may be inadvertently communicating that being female (to the extent that my daughter is able to understand it) is a bad thing.

Anyway, you have to give girls some credit. It’s true that, according to Mattel, one of the most popular games young girls play is “bride,” but Disney found that a groom or prince is incidental to that fantasy, a regrettable necessity at best. Although they keep him around for the climactic kiss, he is otherwise relegated to the bottom of the toy box, which is why you don’t see him prominently displayed in stores.

What’s more, just because they wear the tulle doesn’t mean they’ve drunk the Kool-Aid. Plenty of girls stray from the script, say, by playing basketball in their finery, or casting themselves as the powerful evil stepsister bossing around the sniveling Cinderella. I recall a headline-grabbing 2005 British study that revealed that girls enjoy torturing, decapitating and microwaving their Barbies nearly as much as they like to dress them up for dates. There is spice along with that sugar after all, though why this was news is beyond me: anyone who ever played with the doll knows there’s nothing more satisfying than hacking off all her hair and holding her underwater in the bathtub. Princesses can even be a boon to exasperated parents: in our house, for instance, royalty never whines and uses the potty every single time.

“Playing princess is not the issue,” argues Lyn Mikel Brown, an author, with Sharon Lamb, of “Packaging Girlhood: Rescuing Our Daughters From Marketers’ Schemes.” “The issue is 25,000 Princess products,” says Brown, a professor of education and human development at Colby College. “When one thing is so dominant, then it’s no longer a choice: it’s a mandate, cannibalizing all other forms of play. There’s the illusion of more choices out there for girls, but if you look around, you’ll see their choices are steadily narrowing.”

It’s hard to imagine that girls’ options could truly be shrinking when they dominate the honor roll and outnumber boys in college. Then again, have you taken a stroll through a children’s store lately? A year ago, when we shopped for “big girl” bedding at Pottery Barn Kids, we found the “girls” side awash in flowers, hearts and hula dancers; not a soccer player or sailboat in sight. Across the no-fly zone, the “boys” territory was all about sports, trains, planes and automobiles. Meanwhile, Baby GAP’s boys’ onesies were emblazoned with “Big Man on Campus” and the girls’ with “Social Butterfly”; guess whose matching shoes were decorated on the soles with hearts and whose sported a “No. 1” logo? And at Toys “R” Us, aisles of pink baby dolls, kitchens, shopping carts and princesses unfurl a safe distance from the “Star Wars” figures, GeoTrax and tool chests. The relentless resegregation of childhood appears to have sneaked up without any further discussion about sex roles, about what it now means to be a boy or to be a girl. Or maybe it has happened in lieu of such discussion because it’s easier this way.

Easier, that is, unless you want to buy your daughter something that isn’t pink. Girls’ obsession with that color may seem like something they’re born with, like the ability to breathe or talk on the phone for hours on end. But according to Jo Paoletti, an associate professor of American studies at the University of Maryland, it ain’t so. When colors were first introduced to the nursery in the early part of the 20th century, pink was considered the more masculine hue, a pastel version of red. Blue, with its intimations of the Virgin Mary, constancy and faithfulness, was thought to be dainty. Why or when that switched is not clear, but as late as the 1930s a significant percentage of adults in one national survey held to that split. Perhaps that’s why so many early Disney heroines — Cinderella, Sleeping Beauty, Wendy, Alice-in-Wonderland — are swathed in varying shades of azure. (Purple, incidentally, may be the next color to swap teams: once the realm of kings and N.F.L. players, it is fast becoming the bolder girl’s version of pink.)

It wasn’t until the mid-1980s, when amplifying age and sex differences became a key strategy of children’s marketing (recall the emergence of “ ’tween”), that pink became seemingly innate to girls, part of what defined them as female, at least for the first few years. That was also the time that the first of the generation raised during the unisex phase of feminism — ah, hither Marlo! — became parents. “The kids who grew up in the 1970s wanted sharp definitions for their own kids,” Paoletti told me. “I can understand that, because the unisex thing denied everything — you couldn’t be this, you couldn’t be that, you had to be a neutral nothing.”