"He is out here six days a week and has practice daily," said his father, Mark Williams, who teaches physical education.
We should add that when Griffey has a ball in his hand, he usually wears Stephen Curry gear.
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"When I wear the jersey I feel I can make all the shots," he said.
In Griffey's bedroom, it's all Curry, all the time. But in between the photos, the bobbleheads, the balls, the sweats, and whatever else, there is one item that Griffey doesn't have that he always wanted.
It's one of those official NBA Stephen Curry jerseys.
"He wanted it pretty bad," said is mother, Katie, a San Ramon police officer. And, she felt he should earn it.
So, Griffey set to the task, recycling cans, earning the money a nickel and dime at a time.
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But when the time came to buy it, the young man had a revelation brought on by years of teaching by his family.
"I could have bought it for myself or else for someone who needed it more than I did," he said.
"It gives him the opportunity to earn that money and give to someone else instead of being handed everything," said Katie.
"When he went to the store, there was one jersey," added Mark. "It was him or the kid. He went with the kid."
Fast forward to a meeting on a playground in Oakland. Griffey had never before met Erasmo Merino or his brother Javier, but they all share basketball and a love for Curry.
"Do you have any idea what is going on here?" we asked Javier.
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Blame Griffey's grandma, Eileen McDonald for putting it together. She's with the Alameda County School Board and knew just who to ask about finding that someone in need.
"The call came back in ten minutes. They had just the boy."
It was the unsuspecting Erasmo, a very good, hard-working seventh grader, just like Griffey. He came with his brother, Javier, when their father said he needed them at a meeting.
"They see these things on TV and have said wouldn't it be great if it happened to us?" explained Javier, Sr.
Today, it did. "Merry Christmas," said Griffey, as he presented the jersey and a pair of Curry shoes to Erasmo, along with a pair of Air Jordan shoes to Javier.
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"You see this?" Erasmo exclaimed with disbelief.
Talk about a Christmas surprise. It brought tears to Eileen McDonald's eyes.
"Seeing joy in their eyes. A boy opening something he thought he would never own," she said.
All encapsulated in a timely act of selflessness by her grandson.
Griffey gave up the jersey he always wanted, and exchanged it for something better.
He said it in four words, "The reward of giving."