Before she met Donald Trump at the Kit Kat Club in Manhattan and stepped into a glitzy world of limos and penthouses, diamonds and caviar, Melania Knauss lived quietly.She grew up in one of the anonymous concrete apartment buildings of Yugoslavia when Josip Tito was its socialist leader and over-the-top capitalism, let alone full-blown Trumpism, didn't exist."She never really wanted to stand out or be the center of attention," said Mirjana Jelancic, an elementary school friend in the hilly town of Sevnica in what is now Slovenia.Then she married The Donald.The former high-fashion model started her own "Melania" line of jewelry, marketed a $150-an-ounce moisturizer made with caviar and wore a $200,000 Dior gown at their splashy Palm Beach wedding a decade ago.Now, Melania Trump, 45, who shies away from speaking in public, finds herself directly in the 2016 campaign spotlight, an unconventional spouse of a most unconventional presidential candidate.She would be the first first lady born abroad since Louisa Adams, wife of John Quincy Adams, who moved into the White House in 1825. She is Trump's third wife — another first for a first lady. Ronald Reagan, with a single ex-wife when he took office, was the only other divorced U.S. president.She might also be the most linguistically gifted first lady, as she speaks four languages including heavily accented English. And, without doubt, she would be the only first lady to have posed in the buff while lying on a fur blanket handcuffed to a leather briefcase, as she did aboard Trump's jet for British GQ in 2000."She provides great balance" to Trump, said Roger Stone, the candidate's former political adviser who has known the couple since before they were married. She is smart — "not just an armpiece," Stone said. "She would be the most glamourous first lady since Jackie Kennedy."Melania Trump has been on the edges of political campaigns in the past, as in 2000, when her then-boyfriend briefly sought the Reform Party nomination. During that campaign, she posed in crimson bikini on a rug adorned with the Great Seal of the United States for the now-defunct Talk magazine. And while she has largely maintained a quiet, stand-by-your-man persona, she has at times mixed it up on political issues.In April 2011, when Trump was considering a run for president and was one of the leading "birthers" challenging the validity of President Obama's birth certificate and U.S. citizenship, Melania defended her husband on TV, saying he was "brilliant" and had a "genius's mind.""What's this with the birth certificate obsession? Did he ask to see yours when you met him?" asked television interviewer Joy Behar."Do you want to see President Obama's birth certificate or not?" Melania responded, noting that what she had seen so far was "different" than a birth certificate. "It would be very easy if President Obama would just show it," she said. "It is not only Donald who wants to see it. It's the American people."So far in the 2016 campaign season, Melania Trump has shown more of her homebody side than her provocative one. She only rarely accompanies her outspoken husband as he criss-crosses the country in his private Boeing 757.Friends said she prefers to stay at home — or homes, actually, in New York and Palm Beach — with the couple's 9-year-old son, Barron. On the campaign trail, her 69-year-old husband, who is 24 years her senior, has said that Melania is watching him on TV from home."My wife said something very interesting," Trump said last month on CNN. "She's my pollster, okay?"Trump, who famously obsesses over his poll numbers, said his wife gave him great approval ratings, saying, "'You know, if you actually announce, you're going to win.'"•••Paolo Zampolli wanted to throw a memorable party for his ID Modeling Agency during New York's Fashion Week in 1998, so he chose the Kit Kat Club, a hot Manhattan night spot.He filled the place with models, including Melania Knauss, the statuesque young Slovenian he had discovered working in Milan and Paris.Zampolli said he often traveled through Europe's fashion scene each year, selecting models who had not only the looks but also the temperament to survive the grueling pace of New York modeling.In Melania, he said, he found someone "stable and focused."Melania Knav, who changed her surname to Knauss as her modeling career took off, was not only striking and smart but a practical girl who could sew and "create beautiful clothes," childhood friend Jelancic said.That low-key lifestyle continued when Melania arrived in New York in the mid 1990s, said Edit Molnar, another model and friend. She saved her money and avoided the party scene."She was a homebody," Molnar said in a telephone interview from Paris, where she now lives. "She is completely the opposite of Donald Trump."Molnar said Melania went to the nightclub that evening mainly out of loyalty to Zampolli and her agency. And there, she met Trump, who was out on the town with a date after splitting from his second wife, Marla Maples.Molnar remembered watching Trump fall for her friend. "She is incredible," she recalled him saying. "I want this woman."Melania refused to give him her phone number, but Trump was persistent and left his. Days later, she dialed it.Once Melania was with Trump, she became a hot commodity — especially since Trump was fond of bragging about their sex life.Radio shock jock Howard Stern interviewed the couple by phone in 1999, and, true to his provocative form, he asked Melania what she was wearing. "Not much," Melania said coyly.But her celebrity sex-appeal was cemented by her appearance on the January 2000 cover of British GQ.The icy, blue-green eyes. Plump, pouty lips. Lying seductively on a fluffy fur on Trump's private jet. Wearing a sparkly necklace and not a stitch of clothing. "Sex at 30,000 feet. Melania Knauss earns her air miles," said the magazine's headline.•••The day that Trump announced his candidacy in June, Melania was by his side as he descended the Trump Tower escalator to speak to the cheering crowd below.She was at his side two months later, too, at the first Republican debate in Cleveland. But it is Trump's daughter Ivanka who has spoken out more on his behalf."It's a lot of responsibility for a woman to be married to a man like my husband," Melania told Parenting magazine a few years ago. "I need to be quick, smart and intelligent."In that interview, she said her husband "breathes business," and she loves her role as hands-on mother."We know what our roles are and we are happy with them," she said. "I think the mistake some people make is they try to change the man they love after they get married. You cannot change a person."— Information from the New York Times is included in this story.