By The Book

"Great feeling of calm."

—APRIL 10, FOLLOWING THE FINAL ROUND OF THE MASTERS

If Donald seems more comfortable in his own skin these days a lot of that has to do with his daughter, Elle, a little charmer of 14 months. Even with the challenges of being new parents he and Diane still have a palpable opposites-attract chemistry; she's a lively, funny extrovert who often finishes her hubby's sentences (and sometimes starts them too). Says Christian, "He has life pretty much sorted. He seems more at peace with his place in the game, and having a baby has given him a much broader perspective. He definitely seems to have chilled out."

The caddie change at the end of 2009 is part of that. "It was a slight shock when it happened, but it's for the better," Christian says. "The professional relationship was beginning to affect our personal relationship." After parting ways with his brother, Christian landed Paul Casey's coveted bag, and Luke says of his new looper, John McLaren, "He brings a different personality. He's a little more chatty, he helps me stay a little more lighthearted on course." This is a marked change for a player whom Henrik Stenson calls "proper British."

Golf fans are getting their first glimpses of Donald's winning smile, but he is actually a pretty fun character. With a little cajoling he can do a priceless imitation of dim-witted beefcake Brad Womack, the antihero of the most recent season of the TV guilty pleasure The Bachelor. Donald and a rotating cast of far-flung Tour pros that includes Tim Clark, Charley Hoffman and Carl Pettersson have been known to jack in to the Internet to compete against one another in the video game Mario Kart, the sound track to which is endless chirping among the boys by way of speakerphone. A couple of autumns ago the perfectionist Donald bought a leaf blower. Every day he would blow away mass quantities of leaves from the lawn of his home in Chicago. Every morning he would awaken and survey the endless number that had again fallen on his property. Acknowledging his place in the cosmos, he would mutter to Diane, "They're taunting me." He's an English Premiere League obsessive with a particular passion for Tottenham, which he came by honestly: "Most of my mates growing up loved Arsenal, so I chose to back Tottenham simply to get up their noses."

Donald maybe a little snotty with his pals, but he is also a serious philanthropist. At the Masters he quietly pledged $5,000 for every birdie to Japanese relief efforts. After his productive week he cut a check for $115,000. Donald has donated upwards of $250,000 to Northwestern, where a sparkling golf practice facility is named in his honor. Every autumn he returns to campus to host a fund-raising tournament for his former program, and every February he organizes a match between the current team and alumni at his winter base, the Bear's Club in Palm Beach, Fla. Donald is keen to give back because he remains humbled by how far he has come. Says Diane, the former journalism student, "For a 10-year-old reading this story, what I'd like them to take away is that Luke proves anything is possible. He was just a kid who loved golf and loved playing with his brothers. He wasn't a child prodigy whose parents obsessively pushed him. He had to find his own way. Most of the guys he plays against are bigger and hit the ball farther, but he's Number 3 in the world. And it's just from hard work and believing in himself. That's it."

In his little black binder Donald has been able to boil down his journey into a mere three words: "Believe. Trust. Dominate."

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