Harlan's first trip to see his son in a big league uniform, in Kansas City, brought cheers, then tears. Darren Carroll/SI

Repeat, hour after hour, day after day. See if the boy's passion is as big as his big league dream. See, when he's five, if he'll suit up in the catcher's gear and let the father bounce baseballs off his body. He does. See if he stops playing catch when it starts snowing. He doesn't.

Anoint the boy with a nifty nickname when he's a toddler. Something that makes him feel special even though his home is motherless and his family just scrapes by. Doesn't matter that the kid doesn't know the nickname's meaning. Tell him it was just a sound uttered by his cousin, a two-year-old Winnebago girl who was trying to pronounce the name of her older brother, Joshua, 20 years ago. Joba . Pronounced JAH-buh. So much more dynamic, Joba Chamberlain , than Justin Chamberlain, decides the dad, Harlan. So befitting his dynamic little boy.

Test the boy's legs. See if he keeps his balance through all the tremors at home -- his parents' breakup when he's one, the nearly two years of bouncing from apartment to apartment with his mother and then the ricochet to his father's care thereafter.

Let the son become the father's arms and legs. Have him do the laundry in the basement, where it's difficult for his father to maneuver on crutches, and run to the kitchen for ingredients when Dad fries pork chops and potatoes in an electric skillet next to his living-room chair. Have him and his sister, Tasha, four years older, pull off the father's boots, socks and pants at bedtime, then get the cream, basin and saline water for the venous ulcers on his old man's leg.

Let him grow intimate with weakness so the strength he gains won't be hollow. Here's plenty more opportunity, when the six-year-old boy's father trips over a sidewalk crack at the state penitentiary where he works as a unit manager overseeing security, discipline and sanitation for more than 100 prisoners. Now the problem's not just the polio that Harlan contracted as a nine-month-old, when the 1952 epidemic swept through the Winnebago reservation and left him with a deaf left ear, paralysis in his left arm and leg, and a sunken left shoulder. Now begins the onslaught of post-polio syndrome that often afflicts polio victims later in life, the wholesale atrophying of muscles that knocks Harlan off his feet for good and into a gray three-wheel motorized scooter that he calls Humphrey. A scooter instead of a wheelchair because... well, a wheelchair would make Harlan feel handicapped .

Put the boy in charge of Humphrey. Have him charge its batteries at night. Jump from the van when they arrive at ball fields, pull out the scooter and bring it to his father's side before laying a finger on his bag of baseball gear.

Have him fetch the bases, bats and gloves while Dad motors down the street after dinner, calling to the neighborhood children, "We're playing ball!" and leading them to the field at Sacred Heart elementary, where he'll umpire and coach. Let the boy see his father tip over on curbs and hit the ground without bitterness.

Surround the boy and his sister with disabled people whom the father befriends. Mr. Patocka, a quadriplegic. Mr. Eisenbarth, with bones so brittle they've fractured 50 times. Assign the two children to the booth at the state fair that educates the handicapped on new technologies that might make their lives a little easier.

Tell the boy about the orthopedic hospital in Lincoln where his dad lived for six years, five months and 11 days of his childhood, fighting for his life at first and then enduring the misery of 15 residual surgeries. One in which doctors shattered his good leg in an attempt to keep its growth from outpacing his ravaged left leg's, and a few more when, playing football at age nine, his left knee and hip were so pulverized by a tackle that he ended up in a full-body cast and hospitalized for nearly a year.

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