(CNN) -- New England Patriots players sang "Happy Birthday" to a 6-year-old boy with an inoperable brain tumor Saturday. Daniel Nickerson's visit on the field of Gillette Stadium, where the NFL team was practicing, would be a dream come true for many.Â However, Daniel's biggest birthday wish was much simpler: mail.Â "He just loves getting mail, he's always running to the mailbox," his aunt, Gail Chamberlin, told CNN. A social media campaign by family and friends brought lots of birthday cards addressed to Daniel to the Foxborough, Massachusetts, post office this past week. It also resulted in the Patriots' invitation to their training camp.
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Daniel Nickerson was diagnosed eight months ago with an inoperable brain tumor
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A social media push brought 100,000 letters to Daniel's mailbox
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"He just loves getting mail, he's always running to the mailbox," Daniel's aunt says
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The New England Patriots give Daniel a special sixth birthday honor
While the family is anxious about what they'll learn about the tumor at @placeholder's next doctor's visit Wednesday, Chamberlin said, "He's running around like an average 6-year-old would do, playing."