There is no blatant sibling rivalry between Tiare Cowan and her brother Rick Cowan, nor do stereotypes of birth order apply. The Cowans count many pros and few cons in their business partnership, and for their full-service interior design company, Archipelago Hawaii, it's smooth sailing.

Despite a sagging economy, it's an exciting time for them. “;We're the busiest we've been since starting our business about four years ago,”; said Rick.

They have showrooms on Oahu and the Big Island, are expanding to Maui and have several industry design trophies on their shelves. They also had the spotlight on an episode of HGTV's “;Designer's Challenge”; that aired in February.

Their segment, filmed almost two years ago, focused on the kitchen makeover of an East Oahu waterfront home for which three firms had competed. The lengthy construction process was edited down to a half-hour for the show, which is scheduled to run again on May 25, Memorial Day.

Tiare attributes their company's growth in part to the staff, which is like an extended family: “;They all have a stake here, and we support each other.”;

There's also a certain spirit common to those raised in the islands, she said. “;I can't really explain or put my finger on it, but I think people sense it. They like it and are drawn to it.”;

Their father, David Cowan, is a retired Hawaiian Airlines pilot living on Maui. “;He built his own houses, so we've been around (the building industry) since we were kids,”; Tiare said. Their mom, Lyn Kux, who lives in Kailua, is a semiretired psychotherapist who arrived from California on the SS Lurline, Matson's luxury ocean liner. “;She met my dad on a blind date and never went home.”;

Their father helped the contractor build their first house, in Lanikai, and from then on designed and built his own houses, including one on Maui after the couple divorced.

Tiare, the oldest of five children including a stepbrother, and Rick, fourth in line, are graduates of Kailua High School who spent most of their teen years at the beach—she paddled, he windsurfed—but each had an artistic streak, with Rick being heavy into ceramics.

“;Tiare, when we lived in Lanikai, had her own 'Sunshine Boutique,'”; Rick said.

As a 12-year-old, Tiare used the family garage to sell bathing suits she'd crocheted, dresses and puka-shell jewelry.

“;Yes, I had the entrepreneurial spirit since I was very young,”; Tiare said.

Although they hardly fought, neither did they really relate until young adulthood.

“;We were indifferent,”; said Rick. “;She was in high school ... and I was always this young weirdo she didn't have time for: 'Yeah, I gotta take Rick with us, whatever.'”;

That shifted when Tiare returned from studies at the Colorado Institute of Art. “;We went to a drive-in movie, I guess because she didn't have anyone to go out on a date with,”; said Rick, prompting a laugh from his big sister. “;And we talked the whole time and ended up not watching the movie; it was cool because I never had that experience with her.”;

Their family ties at the workplace are what inevitably pulled each through personal adversity. “;She was going through divorce and had to step back,”; said Rick. Later, when Rick's son needed some extra attention, “;I said, 'OK, Tiare, it's my turn. I'm going to have to step back from the business a bit to get a handle on what's going on at home.'”;

While one took time to regroup, the other ensured the company ran smoothly. A huge corporation might not be as accommodating, said Tiare. “;That's a luxury we had.”;

Her ex-husband had been a business partner, and “;I often felt put in the middle,”; she said, so now “;the company runs smoother.”;

Tiare might be the oldest, but Rick exhibits more first-born, take-charge tendencies, said Tiare. “;I'm more yin and he's yang.”;

“;Tiare's very creative, she looks at the big picture,”; said Rick. “;I like managing. And I need someone to rein me in sometimes, which she does.”;

His propensity to take charge is what spurred their branching out. Tiare had been on a vacation, unaware that Rick had signed a lease securing a showroom in Hilo.

“;I called and said, 'How's everything at the office, Rick?'”; Tiare said.

“;And I said, 'Everything's great, Tiare, everything's fine. ... It's all about expansion, it's all about broadening our scope,'”; he said. “;It was such a great deal for the space. I couldn't pass it up.”;

Tiare was at first overwhelmed by the concept. “;That's where my 'I'm older' reflexes kicked in, and I had to sit him down when I got back and have a talk. But yes, it was all good.”;

As a result, Archipelago Hawaii has showrooms in Waimea, Kamuela and Hilo on the Big Island and will be opening another in Kaanapali.

At the galleries, “;We've teamed up with several other industry partners ... which in this economy is a smart business move,”; said Tiare. “;By creating huis we're not carrying the whole load. Everyone on board gets another footprint, and it's good cross-promotion.”;

Whether their children will follow in their footsteps remains to be seen. Rick and his wife, Luisa Castro, who has her own career at the University of Hawaii, live in Mountain View on the Big Island with sons Rudy and Austin, his son from a previous marriage.

“;Austin is 19 and doing his own thing right now, but Luisa and I built our own house in the back of Kalihi Valley. ... He was 11 at the time, strong enough to carry wood. He helped build that house, putting down flooring, drywall, you name it. Those are skills that maybe he'll be able to use later on in life.”;

Rudy, 6, enjoys drawing and painting, said Rick. “;We do a lot of the work on our own house here. He wants to help me mud and paint, and he loves to go to the showroom.”;

Tiare's two children—Kainoa, 12, and Nai'a, just shy of 11—are also budding artists. “;Kainoa expressed an interest in going into architecture,”; she said. “;Right now he helps me with the upholstery side, strips furniture, makes deliveries, any way he can make a buck.”;

As for Nai'a, she went to school on career day, dressed as an interior designer. “;The good thing about that, I told her, is that you can wear anything you want,”; Tiare said. “;She loves art and wants to go into design. We'll see.”;