His parents explained to Caleb what was wrong.
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Initially, they didn't use the word "cancer."
"We said he had a boo-boo in his belly, in his kidney, in his belly area and that they had to take it out," she said. "Then he had to have medicine to keep it from coming back."
Hawbaker said there wasn't a specific moment when they said, "Caleb you have cancer." The word got introduced gradually, she said.
"He knows now there are people who have died who had cancer," she said. "We keep it under wraps."
Still, Caleb surprises his family with the things he remembers. Sometimes at night, he will crawl into bed with his parents relaying aspects of the ordeal that she and husband, Jeff, find hard to remember.
Then, there are times when Caleb speaks more like an adult — like the time when he was at the end of nearly a month of chemotheraphy that came after doctors removed his bad kidney. He was encouraged by hospital staff to get out of bed and walk.
"All he had to do was get to the chair, which was five steps away and that was a big accomplishment for the day," Hawbaker said. Then they all heard him mumble, "Life is so hard."
"Oh my, gosh, my heart broke because it was like we're just getting started," Hawbaker said. "This was only the beginning. I didn't have any idea what we were headed for, but I knew it wouldn't be fun."
Now that he's feeling better, Caleb has become a voracious reader — at least when Winston's around. The family has a pet dog, a Shih Tzu-Bichon Frise cross named Moses, but Caleb won't read to him.
"He won't stay still long enough," said Caleb, who's in the first grade.
Then he presented the book he was looking forward to reading most, "No, No Jack!"
Jack is the name of a family dog, who had been getting in trouble for hiding things in the family's closet. But in the end, his actions prove helpful.
This was both the first and the last of the four books Caleb read to Winston on Wednesday.
Before Caleb parted ways with his friend, he read the final lines with a moderate, but deliberate pace, "Yes, yes! Good boy, Jack! Dogs do make good friends."