DENVER — The Denver Police Department on Friday unveiled a commemorative badge to celebrate the founding of the department 160 years ago.

Denver Police Chief Paul Pazen presented the badge to the family of fallen officer Celena Hollis at DPD headquarters at 1331 Cherokee St. in downtown Denver. 

"It means everything to us," said Dorothy Hollis, Celena's mother. "We are so blessed. The Denver Police Department, the museum, they're always thinking of Celena, they're always doing things for us for Celena's daughter. It's a great honor."

Hollis was wearing her uniform while working off duty at the City Park Jazz Festival on June 24, 2012 when she was shot while responding to a gang fight by the pavilion next to the lake.

She was 32 at the time and a seven-year DPD veteran.

RELATED: 3 years ago today: Officer was killed at City Park Jazz

Hollis is survived by her daughter, Amyre, who was 12 years old at the time of her mother's death. 

Friday, Amyre's grandmother said she was doing well.

Rollin Oliver, who was 21 at the time of the incident and his arrest, in April 2013 pleaded guilty to second-degree murder. He was sentenced to 26 years in prison.

RELATED: Man pleads guilty in death of DPD officer

Hollis served as president of the Black Police Officers organization and regularly mentored high school girls for Especially Me. Especially Me's mission is to "promote and facilitate ideas, attitudes, goals and lifestyles that will encourage school age youth to adopt and sustain concepts of positive self-value and dignity in defining and pursuing success and excellence," according to its website.

Hollis, who had been assigned to District Two, is buried at Fairmount Cemetery in Denver.

RELATED: Memorial honors fallen Denver officer

Denver Police Sgt. Christopher Hoag designed the commemorative badge.

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