Alex Hammer also got to supervise his 9-year-old sister, Alanna, who was named deputy chief.
"He was giving orders and taking names," their grandmother, Chris Ragusa, told Daily Voice. "He had a ball."
A fire truck pulled up to the Hammer home early Monday with sirens blaring.
Grinning from ear to ear, Alex -- who was diagnosed last November with T-cell lymphoma -- joined his sister for the ride to Town Hall, blowing the horn along the route.
The siblings were later sworn in by Mayor Janet Sobkowicz and, following a special presentation, given a firehouse tour courtesy of Chief Adam Ehrenfels.
"The chief was also gracious enough to have all his crew present to welcome them to the department," Ragusa said.
Alex, who has been in remission, has been extremely popular with emergency responders.
Last Christmas, he got a visit from Santa Claus.
SEE: Santa Visits Sick Boy At His Washington Township Home
Earlier this month, he got to be police chief for a day, joining two dozen or so other children with chronic conditions or disabilities from throughout the county.
SEE: Meet Washington Township’s 4-Year-Old Police Chief
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