USTIN, Texas - The day was hot, the creek was high, and a few of the picnickers had waded knee-deep into the water to cool off. Suddenly, the fully clothed first lady of Texas jumped into the rushing creek, got swept under by the strong current, and then, to the horror of her security men, started floating downstream faster than they could run along the bank.
''She has an independent streak,'' said Adair Margo, a friend who remembers laughing with Laura Bush about the little adventure as the two hung their soaking-wet underwear on the line to dry. ''People say she is shy and reserved, but when she wants to do something, she won't hesitate.''
The American people will meet Laura Bush at the Republican National Convention tonight. But there is a side of the former librarian and schoolteacher, who married George W. Bush because she wanted a little excitement in her life, that they may not see.
She's not the sweetly smiling, seen-but-not-heard spouse who reluctantly embraced her husband's dream of the White House. She's the woman who privately cultivates a rich life outside politics, whether it's bird-watching in Belize, curling up with a great book, designing a dream ranch on the central Texas prairie, or discussing the latest theories on the cognitive development of preschool children.
''She could be your next-door neighbor or your officemate, she is that down-to-earth,'' said Dr. Susan H. Landry, chief of developmental pediatrics at the University of Texas at Houston, who has worked with Mrs. Bush on some of her reading initiatives in the state. ''But she is also impressive - very intelligent, very savvy, and a strong leader who does what she does with warmth and sensitivity.''
Credited with pushing the governor and Texas Legislature to add money for early learning to the federal Head Start program, Mrs. Bush has credentials to address the convention's first-night theme - ''Leave No Child Behind'' - and to talk about education, the signature issue of Bush's presidential campaign.
But make no mistake: Having Mrs. Bush open the Philadelphia convention is really about personalizing the GOP nominee and connecting him to a bright and well-balanced woman. By all accounts, Laura Bush is a happily married mother, an intellectually curious woman, a generous friend, and a political wife who is passionate about her causes, unpretentious in her style, and almost devoid of personal ambition for power.
''Laura is probably the most articulate of all in the Bush family,'' said Ron Kaufman, the GOP committeeman from Massachusetts who is close to the Bushes. ''And living with the governor, witnessing what he has done in Texas, means she understands better than anyone what compassionate conservatism means.''
The convention marks a turning point for the 53-year-old Mrs. Bush, who mostly traveled solo during the primary season, dutifully speaking to GOP women's groups or showing up at elementary schools to read to children.
As soon as her 18-year-old twin daughters leave for college next month, Mrs. Bush will begin campaigning alongside her husband, not just to highlight first family values and her own expertise in literacy and early-childhood education; aides believe George W. is calmer, happier, and more focused when his unflappable wife is around.
Everybody downplays her role as a political adviser. Yet Mrs. Bush tends to turn up at key moments - she was in the kitchen on July 3, for example, when the governor first broached the vice presidency with Dick Cheney - and friends say her husband, whom she affectionately calls ''Bushie,'' confides in her and also relies heavily on his wife to size up situations and measure character.
''Laura has always been someone George looks to for good judgment,'' said Donald Evans, Bush's campaign chairman and one of the couple's oldest friends. ''He knows that she makes the right decisions for the right reasons.''
Because Mrs. Bush generally shuns the limelight, there's gushing in the Bush campaign over her growth and poise in this campaign. The truth is, between the many state and national races run by her husband and father-in-law, she has been in training for this for years. She spoke at the 1996 GOP convention in San Diego, and last month she gave a spirited address to the Texas GOP convention in Houston.
''Politics isn't Laura's life,'' said Regan Gammon, who has been Mrs. Bush's best friend since grade school, as well as her companion on Grand Canyon and Yampa River raft trips and on the bird-watching excursion to Belize.
''She married George Bush, the oilman, and has ended up here as the partner and lifemate of the man running for president,'' Gammon said. ''What could she say but `OK, here we go' and try to make it a positive experience for herself and her children?''
Mrs. Bush jokes that both she and her husband broke their prenuptial vows: He promised she would never have to give a political speech, and she promised to exercise every day. (Aside from the dip in the creek a few years ago and frequent long walks, Mrs. Bush is ''one of the least athletic people I have ever known,'' said Nancy Weiss, an old friend from Lubbock.)
Like the teacher she was, Mrs. Bush does her homework. In an interview late last year, Mrs. Bush said she learned a lot by quietly observing Barbara Bush, but her mother-in-law never gave her advice. ''Barbara Bush realized that daughters-in-law don't want a lot of advice from their mothers-in-law,'' Laura Bush said. ''So I'm sure she had to bite her tongue pretty often.''
In fact, the elder Bushes were delighted when their oldest son, who was something of a playboy and no scholar, declared his love for the 31-year-old Laura Welch, the pretty girl with sparkling blue eyes and a master's degree in library science. In her memoir Barbara Bush said she liked Laura because she didn't try to compete with the others. Asked by one of the hyperkinetic Bushes to cite her interests, Laura said: ''I read, I smoke, I admire.'' (She stopped smoking years ago.)
But friends say it was the extrovert in Bush, the sense that life with him might be exciting, that attracted Laura, a self-described introvert. Both had grown up in Midland - Mrs. Bush was the only child of a prosperous home builder - but they had not met until mutual friends matched them up at a backyard barbecue in 1977. Their courtship was so intense and brief that Laura's parents had to handwrite invitations to the wedding that followed three months later.
Friends always remark on Mrs. Bush's inner strength, something that sustained and guided her when Bush's heavy drinking nearly wrecked their marriage (she told him he had to stop); when a serious case of toxemia complicated her pregnancy with the twins; when her father, whom she adored, died in 1995; and when breast cancer was diagnosed in both her mother and one of her closest friends.
No one will say - certainly not Mrs. Bush herself - how a tragic car accident in 1963 altered her life. When she was a senior in high school, she ran a stop sign in a new Chevy and struck a car driven by one of her classmates. The boy driving the other car was killed; Mrs. Bush was slightly injured. There was no evidence of drinking, a police report said.
Weiss was shocked by the story when a supermarket tabloid reported it recently; she said Mrs. Bush had never mentioned it in the more than 20 years she had known her. ''It was such an acute and painful thing in her young life,'' Weiss said. ''Once she got over the grief, she put it away, and now she just won't go there.''
Protecting her own and the family's privacy has always been paramount to Laura Bush. It has allowed her to lead a fairly normal and independent life - shopping at Home Depot, lunching out with friends, wearing her favorite uniform of jeans and T-shirts. But it also was the reason she was slow to jump on board the Bush bandwagon.
''In a presidential race, there will be characterizations of you that you know aren't true, and there will be rumors that are absolutely not true, but there is no way you can prove they are not true,'' Mrs. Bush said. ''That is something we knew we would have to come to terms with, and so I think we accepted it.''
Once she realized how being Texas' first lady could advance her interests, Mrs. Bush accepted the role with gusto. She is the first governor's wife to have an office in the state capitol - albeit a hard-to-find suite in the basement - and the only one to have achieved a major policy success. Last year the Texas Legislature passed a bill she championed earmarking $17 million for Head Start reading programs.
''Mrs. Bush discovered the power of her office allowed her to do good and fulfill some of her career goals,'' said Margaret LaMontagne, a senior adviser to the governor. ''We've seen a true ramping up in her engagement and comfort with being an advocate. But she never goes into enemy territory.''
She has more causes than issues, and they aren't ones that bring trouble. In addition to early childhood education, Mrs. Bush has found official outlets for her cultural interests by promoting Texas' writers and artists.
An avid reader with eclectic tastes (she just finished ''Gates of the Alamo'' by Austin novelist Stephen Harrigan and is rereading Truman Capote's ''In Cold Blood''), Mrs. Bush organized the first Texas Book Festival in 1996 to showcase the state's authors. Now a must-do event that attracts thousands to the grounds of the state Capitol one weekend each November, the festival has raised nearly $1 million for Texas libraries.
Liz Carpenter, a dyed-in-the-wool Texas Democrat who got into politics working for Lyndon and Lady Bird Johnson, said Mrs. Bush's projects and personality have made her ''beloved and appreciated'' across the state.
''She is someone who will stand by her husband and never embarrass him, all the while doing her own thing,'' Carpenter, 80, said. ''As far as I'm concerned, Laura is the most redeeming feature of George Bush.''
