BOSTON — Boston.--THERE IS a scene in ''Home Alone'' when Kevin McCallister stands before the mirror in his parents' bathroom, slaps some after-shave lotion on his tender 8-year-old skin, and lets out a howl. It comes just in time. One bracing shock of reality, to remind us that Kevin is not quite yet the man of the house.
For the rest of this delicious movie, the son of the suburbs, the youngest child accidentally left behind in his family's frantic vacation exit, is nothing if not self-sufficient. He protects himself. He protects his home. And in the process, it seemed to this contented viewer that Kevin McCallister protects parents from the worst of their anxieties.
''Home Alone'' is a surprise hit. The smart money in Hollywood never figured it would reach the top. They didn't count on the longing for a family movie in which the hero is a delight, the criminals are comic and you don't have put your hands over the kids' eyes.
But it's also a hit because ''Home Alone'' taps the most primal plot: the fears that kids have about being abandoned and the fantasies they have of being on their own.
Kevin is the latest in a long line of deserted children. Before the McCallisters took off for Paris without their youngest son, an entire anthology of children had learned to survive without parents: The lost boys of Peter Pan who had fallen from their prams never to be found again. The children of Disney, Dumbo and Bambi, left motherless.
For a generation, Pippi Longstocking personified a child's fantasy of independence. Even Dorothy, mysteriously orphaned into her Aunt Em's home and then wrenched away by another natural disaster, fended for herself in Oz.
There was never any need for a psychiatrist to analyze this theme. At some point, children become aware of their dependency on adults who aren't always reliable. Parents can be anything from absent-minded to abusive, from benignly neglectful to untrustworthy. Even the best of us can be busy or distracted. Even the most secure childhood can be shattered by death or divorce. This recognition stirs a child's longing to be strong.
The theme has taken a harder twist lately as we fear that family life is coming loose at the seams. Steven Spielberg's fractured NTC families had parents too distracted to see even an ''E.T.'' in their midst. In ''Honey I Shrunk The Kids,'' a harried father absent-mindedly put his children in lethal danger in their own back yard. There was obvious symbolism in the dialogue of the quarter-inch children lost in the suburban grass: ''We're too small. He can't hear us.''
But ''Home Alone'' does more than appeal to the child's need to believe in his survival. Nowadays parents need to believe it as well. And that's what has changed.
At the risk of turning comedy into sociology, Kevin is a poster child for worries about ''self-care,'' that euphemism for no-care. Well over two million kids between 5 and 13 are ''home alone'' every weekday afternoon. Kevin's parents left on vacation, but most have gone off to work. Kevin's neighborhood was emptied for Christmas, but usually it's empty by 9 a.m. Today's working parents, anxious in their absenteeism, set up hotlines and rules . . . over the phone. We talk about childhood ''resilience'' and the value of their ''independence'' -- and keep our fingers crossed.
The movie's upper-class family setting, a houseful of expensive electronic gadgets stands in as a visual accusation often launched against working families: that we are neglecting children for luxuries. Kevin's mother is not the only one who asks herself in crisis, ''What kind of a mother am I?''
Onto this sociological backdrop, steps an 8-year-old boy saying: ''Hey, I'm not afraid any more.'' Kevin on the big screen conquering his fear of the furnace. Kevin taking care of himself. Kevin protecting himself, his home and hearth from criminals who are less threatening than comic.
If ''Home Alone'' is every child's fantasy, it is also every parent's fantasy. It's all there: the universal and anxious wish that, in this uncertain time, the kids will be all right. And the hope for a happy ending.