IN TOUCH WEEKLY reveals Hollywood’s Most Powerful Sisters. They started earning money when they were 9 months old, and Mary-Kate and Ashley Olsen, now 22, have never stopped. As co-presidents of Dualstar Entertainment Group, the twins have an estimated combined net worth of $100 million and they oversee an empire that sells $1 billion per year in clothing, books, furniture, videos, dolls and a slew of other merchandise. “We couldn’t do this if we weren’t best friends,” says Ashley. “If we weren’t really close, we’d rip each other’s heads off.” “We do everything for our company,” says Ashley. “In that sense, we feel powerful.” “It wasn’t about acting. It was about making kids smile,” says Mary-Kate of the twins’ early roles. The Olsens were self-made millionaires by the age of 10. “We have the same ultimate business goals,” says Mary-Kate of sister Ashley.

Mary-Kate and Ashley Olsen like to be in charge

2. Jessica & Ashlee Simpson

Ashlee inherited Jess’ business skills

“An older sister sets the path,” says Ashlee Simpson, who has clearly learned the art of how to market the family name from her big sis. Jessica’s makeup, perfume, clothing and shoe licensing deals make millions, and now Ashlee, 23, has partnered with Wet Seal to design her own line of tops. The two earned a combined $50 million a few years ago, but Jessica, 27, does all she can to keep her ego in check. “Nobody deserves to be treated like a princess 100 percent of the time,” she says. “Not even me!” In 2006, Ashlee turned down $4 million to pose nude in Playboy. She said she could make that kind of money “somewhere else.”

3. Britney & Jamie Lynn Spears

Britney and Jamie Lynn are in demand

“My advice to Britney is to just scoot over, ’cause I’m coming through,” Jamie Lynn Spears, 17, once warned. But while ratings for her show Zoey 101 doubled after her pregnancy was announced in December, her sister, 26, remains the bigger star and breadwinner. “I like money,” Britney once put it simply. And even after her recent financial woes, it’s estimated that she retains about $50 million of her former net worth of $125 million, thanks to past endorsement deals with Pepsi and McDonald’s, among others. Britney is responsible for boosting the U.S. economy each year by an estimated $120 million, even when she’s not on tour.

4. Beyoncé & Solange Knowles

Beyoncé and Solange team up

Beyoncé, 26, is a top music and film draw who made $80 million in the past year. Solange Knowles, 22, has also made her name in the music industry, while helping dad Mathew create the Baby Jamz urban toy line. And both sisters have pitched in with mom Tina in creating and marketing the family fashion line, House of Deréon. “I never imagined I’d be so blessed,” says Beyoncé. “I just wanted to be financially stable, and it embarrasses me.” “In five years, I’ll be answering those calls. I’ll be president and CEO,” says Solange, about inheriting the Knowles music empire.

5. Hilary & Haylie Duff

Hilary and Haylie want to do it all

Hilary Duff has made more than $25 million from her films, CDs, music tours and Stuff by Hilary Duff fashion line. “My life is kinda like a fairy tale,” admits Hilary, 20, who was recently made into a Sims character. Big sister Haylie, 23, also sings and acts, and is currently hosting Legally Blonde the Musical: The Search for the Next Elle Woods on MTV. Still, sibling rivalry is a family no-no. “My dad always said, ‘If you ever fight over a part, you guys have to come home,’” Haylie explains. “My sister and I are best friends and we get along well,” says Hilary of Haylie. “She’s so talented and inspiring.”

6. Paris & Nicky Hilton

Paris and Nicky are shrewd marketers

“Fashion is my priority,” says Nicky Hilton, 24, who runs two clothing lines, Nicholai and Chick, and is at work on her own furniture line. Sister Paris, 27, meanwhile, has earned millions by making public appearances and licensing her name to everything from perfume to watches to alcohol. “It’s always been my dream to build my own empire — and I’m doing just that,” Paris tells In Touch. “I feel like I have to work twice as hard to prove myself,” says Nicky. “I’m not content doing nothing.”

7. Venus & Serena Williams

Venus and Serena score big off the courts

“I’m not a tennis superstar,” insists Serena Williams. “I’m a superstar. Period.” Both she and Venus, 28, have many lucrative endorsement deals, as well as their own fashion lines. Serena, 26, has also acted on ER and The Game, while Venus runs her own interior design firm. “You have to be willing to try big things to achieve big things,” says Venus. “If you want it, go for it,” says Venus of the secret to success she shares with Serena.

8. Lindsay & Ali Lohan

Lindsay and Ali started young

“I work harder than anyone I’ve ever met in my life. And I enjoy it,” says Lindsay Lohan, 21, who landed on Forbes’ list of top-earning young superstars last year, earning $3.5 million. And little sister Ali is hot on her high heels. “Lindsay’s my role model,” says Ali, who got into modeling as a toddler, then quickly moved on to acting and singing. At just 14, she’s already working on her second CD, starring in her own reality show, Living Lohan, and filming her first movie, Mostly Ghostly. “The best gift Lindsay gives me is when we are together,” says Ali of her big sis.

9. Ashley & Jennifer Tisdale

Ashley and Jennifer are on the rise

“Some girls think acting is glamorous, but it’s hard work,” says High School Musical’s Ashley Tisdale, 22. And hers is paying off. She’s made $5.5 million in the past year, is about to release her second CD and is in negotiations for her own film-production deal. Jennifer, 26, star of Bring It On: In It to Win It, hopes for the same success. “She’s the star of the family,” Jennifer says. “But I don’t mind at all. She’s my best friend.” “We call each other out on our diva moments,” says Jennifer, about keeping it real with Ashley.

10. Kim, Kourtney & Khloe Kardashian

The Kardashians are in fashion

The Kardashians — Kim, 27, Kourtney, 29, and Khloe, 24 — may lead glamorous lives, but they also have a strong work ethic. “We knew when we were 18, we were cut off,” says Kim, who has her own workout video and is now breaking into acting. “We grew up with privilege, so our standards were high. And if we wanted to keep that, we had to work hard.” So they all do, tending to every detail at their Dash and Smooch boutiques and starring in E!’s Keeping Up With the Kardashians. More than 13 million people caught up with Kim, Kourtney and Khloe on their E! reality series during its first month.

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