He received the honor after beating a different type of enemy: cancer.
Diagnosed at age six with acute lymphoblastic leukemia, Grimmett underwent three and a half years of chemotherapy, grueling treatment for a brave little boy.
It included spinal taps and blood transfusions. And now that Douglas has beaten cancer like a boss, he got to be the boss on Tuesday.
"I'm grateful for this opportunity today because I got to meet Sheriff Toulon, who is also a survivor," Douglas said. "And I get to be the Suffolk County Sheriff for a Day."
Suffolk County Sheriff Errol Toulon is a two-time cancer survivor himself, a big factor in why the Leukemia and Lymphoma Society thought this was a great fit in granting Douglas's wish.
"The sheriff has really inspired all of us," said Sara Lipsky of the Leukemia and Lymphoma Society. "He is a two-time cancer survivor and his personal story really connected with Douglas."
A connection both are happy they're healthy enough to savor for a lifetime.
"As a former cancer survivor, I'm getting a little emotional....but i'm happy, ok," said Toulon.
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