Britney's Wild Year

Before her Onyx Hotel tour kicked off – and was abruptly canceled because of a knee injury – Britney Spears began the year dazzling an audience in Cannes.

When Britney wed backup dancer Kevin Federline in a surprise ceremony Sept. 18, she also became a stepmom to his daughter Kori, 2, and son Kaleb, born in July (not pictured), both by his ex-girlfriend, former Moesha actress Shar Jackson. As for Britney, "I want to be a young mom," she told PEOPLE after marrying Federline. "Next year at 23, I am so there."

Along with an eye-catching gold minidress, Spears sported a red-string Kabbalah bracelet on the red carpet at an event in Cannes in January. The bracelet, a hallmark of the mystical Jewish practice embraced by Britney's pal Madonna and celebs such as Demi Moore and Ashton Kutcher, is said to ward off evil.

Britney often communicated her moods via T-shirts in 2004. Her "Mrs. Federline" tank, which she wore about a month before the couple tied the knot, got the rumor mill running overtime. The "Brunettes are so hot right now" tee reflected the usually blonde bombshell's time on the darker side. And her "I'm a virgin (but this is an old T-shirt)" top poked fun at her earlier promise to save herself for marriage.

Britney joined the ranks of stars such as Jennifer Lopez, Paris Hilton and Donald Trump in launching her own fragrance, Curious, on Sept. 14. Other products in Britney's line include "Deliciously Whipped!" body souffle and "Lather Me Up!" shower gel.

In the wee hours of Jan. 3, after watching The Texas Chainsaw Massacre in their $10,000-a-night suite at the Palms Casino Hotel in Las Vegas, Britney and her childhood pal Jason Allen Alexander tied the knot at A Little White Wedding Chapel. The marriage, which was annulled on Jan. 5, lasted 55 hours. "That thing was a total ugh," Britney told PEOPLE later. "I was not in love at all. It was seriously my friend from home and we got crazy in Vegas."

Britney and Federline set off a media frenzy when they frolicked on a Santa Monica, Calif., beach in April. A source close to the pop star denied there was a relationship, saying at the time, "Britney's just having fun." But after the pair became engaged in July, Spears told PEOPLE: "I knew instantly. I kissed a bunch of frogs and finally found my prince. I feel like I've found my happily ever after."

On the mend from her tour-ending knee injury and just back from a week in Hawaii, Britney showed off her bronzed, fit figure at a hotel pool in L.A. in July. "I was ready for a little break," Britney said. "It had been a great tour, but my head wasn't really into it."

"I definitely want to have some kids," Spears told PEOPLE after she and Federline announced their engagement. "We're starting with a dog." Make that two: Along with Chihuahua Bitbit (left), Britney has been cradling another furry friend and a Maltese named Lacy (right).

Britney and her mother, Lynne Spears (in New York in December), kept up their close ties in 2004. In her Thanksgiving letter to fans posted on her Web site, Britney praised Lynne as a "Supermom": "Living in a small town can make it so easy to just follow the mold and go along with how everyone else does things," she wrote. "But my mom managed to set her own course and not get corrupted into doing things like all the other women."

During her time off from working, Britney often displayed a more slovenly side in 2004 (such as here, in a Malibu parking lot in August). Britney's mom scolded the press for publishing unflattering pictures and defended her daughter: "The doctor's orders are for her to wear Uggs or tennis shoes, and it's just too hot for that," she wrote in a statement on Britney's Web site. "Sometimes it just feels good to go barefoot in this heat and give her feet a rest."

Britney's brother Bryan got a special treat at his 27th birthday bash in April: His famous sister arranged for actress Carmen Electra and her Pussycat Dolls burlesque group to put on a sexy 20-minute show for him. Clad in a Pussycat Dolls' costume, Britney herself sang "Happy Birthday" a cappella. But first the pop princess hired actors to pose as FBI agents, arrest Bryan, handcuff him and take him to L.A. club Space, where 50 friends shouted, "Surprise!"

On June 8, the pop star slipped and tore the cartilage in her left knee while filming a video for her single "Outrageous" in Queens, New York. The injury suspended production of the video and caused Britney to cancel the remaining 37 shows of her Onyx Hotel Tour, likely costing her "tens of millions of dollars," Billboard senior writer Ray Waddell said at the time. "She would have been one of the top-grossing tours of the year had she played it out."

Britney joined fellow pop divas Beyonce Knowles and Pink in a multimillion-dollar Pepsi ad campaign in January, in which the gladiator-fashioned singers decide not to fight each other in a Roman-style coliseum, but instead turn on the emperor (played by Enrique Iglesias). In the ad, the women sing Queen's "We Will Rock You" and rally the crowd against the emperor, who is eventually thrown to a stalking lion in the arena.

Britney, who is close to her lookalike 13-year-old sister, Jamie Lynn (right, with a fan in Destin, Fla., in April), encourages her career aspirations as an actress. "Jamie Lynn is turning into such a beautiful little lady. Her new show is coming out soon and I am sooo proud of her," she wrote in a Nov. 8 letter to fans, referring to Zoey 101, which stars Jamie Lynn and debuts in January on Nickelodeon.

In her first public appearance since marrying Federline, Britney, her new hubby and their dog Bitbit (wearing a $100,000 Lorraine Schwartz diamond cuff) wowed the crowd at the Billboard Music Awards on Dec. 8 in Las Vegas. Along with presenting Kanye West with the rapper of the year award, Britney took home the hot dance sales single of the year award for "Me Against the Music," her collaboration with Madonna.