Superstar and suburban hausfrau Jaclyn Smith is kneeling next to her son's white marble bathtub, the sleeves of her oversize canary yellow sweater rolled into donuts at her elbows. She is allegedly bathing her frisky son, Gaston, just out of his Terrible Twos. But splish, splash, it's Mom who's taking the bath. Even with no makeup, sagging curls and dressed in khaki tan pants and red high-top sneakers, Smith radiates a natural, incandescent beauty. This only confirms what her pal Jane Seymour observes: "When I do my mothering, I pull my hair back into a ponytail and go for it. When Jackie mothers, she still looks like a cover girl."

Meanwhile, Gaston flails away.

"Please don't do that, honey," Smith pleads, in a sweet Texas drawl. Gaston, knowing his mother for the pushover she is, flails some more.

"Okay, love bunny," she says with mock seriousness. "You better mind your p's and q's."

"What's p's and q's, Mom?" he asks.

"It means be a good boy, or your father will come up here," she says and then cracks up. Moments later she dabs him dry with a fluffy towel, like the ones she used to bring from home for him when they traveled. It seems she didn't want hotel towels touching his "sensitive skin." (This makes her perhaps the only person ever to bring towels into a hotel.) Now she looks back at her overprotectiveness and laughs. Sort of. "I was driving everybody crazy, handwashing the towels," she confesses. "Now he uses the hotel towels. I'm better." Almost.

Despite a phalanx of household help, they haven't invented the nanny who can peel Gaston from his mother when she's not working. Confirms her husband, British cinematographer-director Anthony Richmond: "It would be easy after 14 hours of shooting for her to say 'I'm tired' or 'I'm going to bed.' But Gaston comes first." Adds Smith, who was 35 when Gaston was born: "You don't want to be away, you don't want to miss a moment." She hasn't. Gaston's life may be more documented than World War II: Pictures of her blue-eyed only child (they want more)dot her bedroom; "major events" (such as when he started nursery school) are noted by her secretary on a special calendar; two of his three birthday parties are on videotape, and in a sweetly sentimental gesture, Smith writes What-a-Year-You've-Had letters to him on each birthday, which she'll keep stored in a safe until he is 21.

At 38, her professional life has never been as full. In the space of four months, she has four projects coming to fruition—a three-hour NBC TV movie (Florence Nightingale) on Easter Sunday, her first feature )(Déjà Vu, directed by her husband) next month, a just published beauty book (The American Look, How It Can Be Yours) and a new clothing line due in August. While her acting has yet to be mentioned in the same breath as, say, Ethel Barrymore's, her fetching beauty should earn her status as a national landmark. And as a loving mother, she makes Maria von Trapp look like Ma Barker. But then, her mother, Margaret Ellen, back in Houston, is some role model. On Valentine's Day, recalls Smith, Mom would pack heart-shaped sandwiches for her schoolgirl daughter and dye the bread pink. As a teenager Jackie carried her dolls in paper bags, embarrassed because she was too old to be playing with them. Five years ago, perhaps as a kind of dry run for motherhood, Smith had her Standard poodle, Vivien Leigh, artificially inseminated with sperm from her other beloved poodle, Albert. "I was dying to have Albert's puppy," she explains. "He traveled the world with me, but he and Vivien never seemed to make love." The result was an eight-puppy litter; she kept one and named him Richmond, after Tony, and the rest were given to friends and family.

The dress rehearsals for motherhood paid off. Since Gaston, "My work is better, my life is better, and my feelings about myself are better," she says. Even the shape of her face has changed, she says: It's more square, and her cheekbones are better. "If I find myself complaining or saying I don't want to do something, he walks into the room and I think, 'Wait a minute. This is what it's all about. Let's keep the priorities straight.' " Gaston started nursery school in February, and the separation was "harder on me than on him," she says. "When I'm not with him, it's almost like withdrawal."

Now she has good friend Farrah Fawcett, 38, to trade diaper stories with. Farrah and 2-month-old Redmond James Fawcett O'Neal were guests at Gaston's third birthday bash three weeks ago. "When I saw Farrah coming in, it brought tears to my eyes," Smith says. Farrah also probably wanted to return the maternity dresses Jackie loaned her during her pregnancy. Hey, what are good friends for? Farrah, says Smith, "is a very good, very relaxed mother," has regained her shape and is "thinner than ever." As for young Redmond, "He's a very pretty baby with reddish-blond hair." That leaves only one original ex-Angel, Kate Jackson, 35, babyless. Smith is her chief cheerleader. "I saw her at Night of 100 Stars last month and said, 'Oh, Kate, now it's your turn!' "

Smith is stretched out on a chaise, which is covered in her favorite English chintz floral fabric, in the elegant parlor of her 11-room French Colonial Bel Air home. Her books and magazines validate her image as a homebody: English Interiors, Estates of Beverly Hills, Architectural Digest. The air has the sweet aroma of a mixed bouquet of freshly cut flowers from her garden. She is warm and friendly but chooses her words carefully. Her hospitality reflects her well-bred Southern upbringing: Mrs. Field's chocolate chip and oatmeal cookies appear on a silver serving tray. And the dainty white cloth napkins, embroidered in pink flowers and trimmed with blue stitching, seem more deserving of slipcovers than somebody's mouth. "I'm on a diet, but I'm going to have one anyway," she says, nibbling at a cookie.

Better now than last fall, when she was in England filming the story of 19th-century British nursing pioneer Florence Nightingale. Then she was cinched daily into a corset that shrank her waist to a mere 21 inches, torture even for a size 6. For the Crimean War scenes (in rat-infested hospitals), Smith wore no makeup and "they added red to my eyelids, and wrinkles. I looked like death." She's hoping the drama will boost her credibility, much as The Burning Bed did for Farrah.

Her credentials are more secure in the beauty department. She's just signed on for two more years as a Max Factor spokeswoman, and as of August 1 she'll join the ranks of such celebrities-turned-designers as Cheryl Tiegs and Christie Brinkley, when her own line of Jaclyn Smith clothes turns up in 1,400 K mart stores around the country. Her coordinated separates will sell for $16.97 to $24.97, not far from what she pays for her favorites like Bill Blass, Ralph Lauren and Fabrice, give or take a few decimal points. She is not exactly intimate with that time-honored call, "Attention K mart Shoppers!" But Jackie insists she has a mission. "I have a chance to give people nice-looking clothes at a price they can afford," she says, insisting, "I am going to wear them!" Take that, Sears.

On the Hollywood party circuit, Smith and family are all but missing persons. "Tony says we need to cultivate more social life," says Smith. Not surprisingly, they both prefer nights at home with Gaston. Nights out are usually limited to a movie (Witness is a recent favorite), but she won't see any movies that tell "depressing" tales about children. "I came out of Terms of Endearment and said, 'Why did I do that to myself?' " Nights in are for cozy dinner parties. It is Tony—when their own cook isn't around—who rules the kitchen, and they have installed a restaurant-quality stove for him. "I'm not a good cook," Smith says. She pauses. "Actually, I'm a disaster. If somebody said, 'Would you rather your husband give you a Rolls-Royce or cook, I'd say cook.' "

But it's more than his palatable pork chops that Smith finds appealing. After her divorce from second husband Dennis (The Young and the Restless) Cole, she went through a depression because of a "strong sense of failure." With the savvy but "outspoken" Richmond, 41, her third husband, she has found someone "who loves the same way," and values home and family as much as she does. (He has three children from a prior marriage living in London and sees them whenever he can.) "I can't say that every moment is easy or that it's Snow White and Prince Charming," allows Smith. "But what I realize is, yes, we have a family, and we're working toward something together. In my other marriages I never had that. We were not a unit." She still believes in marriage. "I'd do it again if this one didn't work out," she says.

After Gaston's birth, Richmond was inadvertently a victim of postpartum neglect. "Everything else in my life took a back seat," she says. "Tony was wise enough to see this. He said, 'There's another person in this house. I need attention. I'm jealous.' I realized I was being unfair." Richmond has forgiven her. "Jackie always wanted a child," he says, "and I think all mothers go through that with their first."

Next month, the pair is planning a getaway cruise on the QE2. When they return, there will be no shortage of work. Richmond, who hopes to direct more features, will be directing her K mart and Max Factor TV ads, and she's negotiating to do a sequel to Rage of Angels, her smash 1983 TV movie. They're also working on projects for their Smith-Richmond production company, which has a three-picture deal with CBS. (The networks rejected her idea to play Gone With the Wind author Margaret Mitchell in Road to Tara.)

To outsiders she seems immune to the push-pull stresses of other working mothers. But, says her friend Jane Seymour (whose daughter Katie, 3, and Gaston are friends), "We talk endlessly about how complicated it is to mix business with children's lives." Still Smith, like the beer commercial, says you can have it all. "You have to have the right kind of man and want to have it all more than anything. You have to be willing to make sacrifices, be a little tired and not have as grand a social life." You also have to take a realistic view of your career, which Smith—all but alone among the stars of Hollywood and Burbank—seems to do. "I don't have a desperate feeling about my career. If I stay in television and if I'm proud of what I do on TV, that's fine." And having a son seems to lend a sense of fulfillment to her work that eluded her before. "I've never been offered more, never gone in more directions," she says. "Everybody has fantasies. I feel like I'm living mine." Farrah, take note: This is what you have to look forward to.