AS the new president of the American Bar Association, Talbot D'Alemberte is accustomed to receiving calls from the press. But nothing could have prepared him for a call two weeks ago from a reporter informing him that his daughter appears semi-nude in the October edition of Playboy magazine. Gabrielle D'Alemberte, a student at the University of Iowa, poses as one of "The Girls of the Big Ten," wearing only a smile and a pair of unzipped denim shorts.Daddy's little girl in Playboy. What's a father to do? Mr. D'Alemberte made no effort to hide his disappointment. A supporter of women's rights, he admitted to one reporter that the Playboy philosophy is "quite contradictory" to his standards and that Gabrielle's decision would not have been his choice. To another interviewer he acknowledged that she is an adult and he does not control her. "I'm not sure what parents do to change their children's feelings at this age," he said. The same week, D'Alemberte, a liberal Democrat, learned from the New York Times that his daughter is a Republican. He joked, "I'm not sure what is going on in her mind. And I'm not sure which decision disappoints me the most." D'Alemberte probably does not consider himself a role model for parents. But with his grin-and-bear-it candor - his willingness to let his embarrassment, hurt, and love show through - he undoubtedly gives comfort to other fathers and mothers whose children have not followed the path parents would have chosen. For her part, Gabrielle D'Alemberte admits her father is "not happy." But, she says, "He realizes that I'm 21 years old and very capable of making judgments for myself." As youthful indiscretions go, Ms. D'Alemberte's body-baring fling in Playboy is minor, if all too public. She broke no laws. She did not endanger herself or others. And she probably did no irreparable damage to her ambitions to be a lawyer. What one generation might classify as rebellion, another generation chalks up to experimentation or adventure. Children are the original Baltic states - miniature breakaway republics eager to declare their independence from the mother country. September, in fact, ranks as a prime breakaway month, and not just in Eastern Europe. From kindergartners skipping off to their first weeks of school to college students savoring the heady freedom of campus life, the process of transferring responsibility from one generation to another goes on. Playboy is not the only place to find evidence of relinquished parental control. Any careful reader of wedding announcements in newspapers can imagine the family adjustments hidden behind the photos of at least a few smiling couples. A random list could include the groom, a Yale graduate, who lists his occupation as guitarist in a rock group. The philanthropist's daughter who marries a contractor's son. The bride, a daughter of two professors, who never went to college. The couple whose ceremony is condu cted jointly by a rabbi and a priest. And the pair whose marriage brings together two cultures. In all these unions, who knows what parental dreams have been revised on the way to the altar? Surveying his loving discontent, D'Alemberte says: "Most of us who've been parents have been through some heartache, and most of us who've been young have made mistakes ourselves." Since parents have been on both sides of the divide, the burden must rest on them. It is their bittersweet purpose to design their planned obsolescence - to encourage and educate their children into an independence that must include independence from their parents. Parents know, as children cannot, that independence comes with a price, as in the case of the Baltic states. Despite this foreknowledge, and despite the doomed parental instinct to treat the fledgling's life as a projection of its parents', th e thoughtful mother and father are honor-bound to respect a child's sovereignty. Do my children have good hearts? Are they happy with the lives they are living? Are they successful by their standards of success? These are the concerns ideal parents limit themselves to. Since parents - and children - are seldom ideal, the struggle to keep possessive love and anxiety within bounds goes on. As D'Alemberte illustrates, to understand the comedy of family life nurtures the love and minimizes the anxiety.