Editor's note: CNN contributor Bob Greene is a best-selling author whose new book is "Late Edition: A Love Story."

Seven-year-old Wyatt Wilke wanted to be a Marine and a doctor.

(CNN) -- On the morning of last year's annual Sunflower Fair in La Porte, Indiana, a family, appearing a little lost, walked up and down a crowded street, looking in vain for the table to sign up their entry. They carried a large sunflower with them.

If no one noticed the exhausted, grieving look in the family's eyes, that was understandable. The Sunflower Fair is a place of happy noise: rides and music and food booths. It is La Porte's fall festival, and people from across northwest Indiana come to spend a Saturday in the midst of the milling, chattering crowds.

The family silently bearing the large sunflower had never been to the fair before.

But this was important.

They finally located the entry table, and asked for a form. They carefully filled it out. Their flower was entered in the seed head category -- the one that judges the largest seed head, which is the circular area in the middle of a sunflower.

They wrote down the name of the person who had grown the sunflower:

Wyatt Wilke.

He was their 7-year-old son. He had died earlier that same day, at a few minutes after midnight.

Now, less than 10 hours later, here they were, with Wyatt's flower.

"He loved growing his sunflowers," said his mother, Cathleen Wilke. "Every year we talked about coming into La Porte for the Sunflower Fair, but we never got around to it. Wyatt really wanted to be part of the contest."

That's what they had planned -- a day at the fair, to enter his sunflower. He was a healthy, constantly laughing boy -- he loved school, where he was in the second grade, he loved horses, he loved his big brother John, with whom he shared a bedroom. The Wilkes lived in the tiny town of Hamlet, about 15 minutes from La Porte; Wyatt would look out the back window, watching for blue jays and cardinals.

"He planted his sunflowers in our garden," Cathleen Wilke said. "He was so careful with them. A few weeks before the fair, there was a heavy windstorm that knocked his biggest sunflower over. He called to me: 'Mom, it's on the ground -- my flower, it's down.' He was afraid it was ruined. But he managed to save it."

The week before the fair, Wyatt wasn't feeling well in class -- he had a sore throat. The school called on a Wednesday. He came home.

"But the next morning, he was up, and he wanted to go to school," his mother said. "He was always so responsible -- he said, 'I didn't get my homework done last night.' I told him that was all right, that the school would understand. But as I made him his toast, he sat there on the couch, doing his homework."

She told him he really shouldn't go to school. He stayed home. That day, he seemed to get sicker and sicker.

"We drove over to the hospital in South Bend that night," his mother said. "He was talking in the car. As sick as he was, he said to us: 'Mom and Dad, when are we going to get to go camping?' There was this big, round, moon in the sky, and he looked out the window of the car and told us to look at it. He said the moon was so beautiful."

At the hospital, they knew he was in very bad shape. Wyatt, it would turn out, had contracted an overwhelming bacterial infection that had entered his bloodstream and that was attacking his organs. He was in the hospital that Thursday night and all day and all evening Friday. His body went into septic shock; it couldn't fight off the infection. Friday turned to Saturday. His life ended just as the new day began.

"He had always told us he wanted to grow up to be a Marine," his mother said. "Then he said he wanted to be a doctor. So we told him he could be a Marine doctor."

And now they were at the hospital, and at age 7, he was gone.

Someone remembered: This was going to be the day of the Sunflower Fair.

How they found the strength to do it is hard to conceive. But that morning, carrying Wyatt's favorite sunflower -- the one he had saved when the wind had knocked it down -- they were at the fair in La Porte.

They waited together as all the categories were judged. No one around them had any idea.

And then, through the loudspeaker system at the fair, the winner of his category was announced:

"First place. . .Wyatt Wilke."

The judging committee looked around, waiting for the winner to come forward and accept his trophy.

His family. . . .

Well, you can imagine.

"I don't even remember which one of us went up to accept it for him," his mother said. "But Wyatt had won. He had won."

That was a year ago. A few months later, the fair's organizer, Phyllis Jones, approached Cathleen Wilke and asked her if she would like to serve on the committee. She said yes.

And this year at the fair, the contest -- all the categories, the whole competition -- had a new name:

The Wyatt Wilke Sunflower Contest.

The seeds from Wyatt's winning flower were given to his classmates at Kingsford Heights Elementary School. The children planted them in the school's new memorial garden, the one that is named for Wyatt.

The sunflowers are blooming now. Soon enough winter will arrive, and the snow will cover Indiana. But the seeds will be planted in the school's garden every year, and forever the flowers will return, bright and vibrant and full of life's very best promise, like the smile of a boy who believes he can do anything.

The opinions expressed in this commentary are solely those of Bob Greene.

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