Estella Barrett, the aunt of Tina Kerbrat, hugs the fallen officers son, Craig Kerbrat. Friends, family and fellow officers of Tina Kerbrat gathered for a memorial ceremony on Feb. 11, 2011 at the North Hollywood Police Station on the 20th anniversary of her death. (John McCoy/staff photographer)

A memorial service Friday in North Hollywood marked the 20th anniversary of the day that the first female Los Angeles police officer was killed in the line of duty.

Officer Tina Kerbrat was killed in Sun Valley just four months after graduating from the Police Academy and the day after her 45th birthday. She was on patrol with her partner when they pulled to the curb to investigate two men who appeared to be drinking beer in public.

As she about to get out of the patrol car, one man charged the vehicle and fired several shots from a .357 Magnum, killing her instantly. Her partner shot and killed the gunman, Jose Amaya, 32, an illegal immigrant from El Salvador.

Kerbrat's daughter, Nicole, was 3 years old at the time.

Estella Barrett wears a badge with her niece's number on it. Friends, family and fellow officers of Tina Kerbrat gathered for a memorial ceremony on Feb. 11, 2011, at the North Hollywood Police Station on the 20th anniversary of her death. (John McCoy/staff photographer)

"For me, the hardest thing has just been always having that question in the back of my mind, kind of, what if my mother had always been there?" Nicole told KCBS (Channel 2).

"She was just so full of life; and I have yet to see one picture that she's not smiling in. She already had a pretty wonderful life, and still went above and beyond to be a police officer, and followed her passion."

Among those attending the ceremony were LAPD Deputy Chief Kirk Albanese; Kerbrat's widower, Tim; and her son Craig, who was 6 when his mother died in 1991.

"I still have pictures of her in my room," he told Channel 2. "I still have memorabilia of her. She was a great mom ..."

LAPD Chief Charlie Beck was a sergeant at the time of Kerbrat's killing.

"She still had so much ahead of her, and (was) at such an early stage of her career," Beck said. "When Tina was killed, it shocked the department," he said. "It wasn't that she did something wrong, or was in the wrong place. She was doing what she was supposed to do. We honor our past, and Tina's a big part of that."

This spring, the LAPD Women's Running Team will compete in Kerbrat's honor during the 27th annual Baker to Vegas Challenge Cup Relay.