Over the years, Lindenwold Patrolman Hugh A. Shannon's death on Christmas Eve in 1946, caused by a hit-and-run driver as he directed traffic on the White Horse Pike, was mostly forgotten. His daughter who witnessed the accident and died 20 years ago rarely spoke of it. With each passing generation, even family lore grew short on details.

Until recently, few borough officers knew he was the only officer killed in the line of duty in the department's 83-year history.

His death, while still a sworn officer at age 72, would likely have remained a footnote, until a man from New Jersey met a woman from New Jersey in a hotel in New Hampshire about a decade ago - and a persistent Lindenwold lieutenant refused to abandon a quest to honor a fallen brother who was known as "Pop" to children he helped cross the Pike.

Earlier this month, Shannon's name was carved into the National Law Enforcement Officers Memorial in Washington. On Sunday, Shannon and nearly 400 other fallen officers will be honored in front of 20,000 people who are expected to gather on the memorial grounds in Judiciary Square for a candlelight vigil. Those who cannot be present can watch a live stream of the ceremony.

U.S. Attorney General Eric Holder is to give the keynote address. About 1,400 officers from departments nationwide, including in South Jersey and Pennsylvania, will ride bicycles to Washington as part of the annual Police Unity Tour to attend the dedication.

The 362 honorees this year include 163 who died in the line of duty in 2011 and an additional 199, like Shannon, who died earlier.

"Any officer that's killed in the line of duty, they should be honored. They should have a lasting memorial so they're not forgotten," said Lindenwold Lt. Michael McCarthy Jr., a 14-year department veteran who submitted an application in December to have Shannon's name added to the memorial.

Since its dedication in 1991, 19,000 fallen officers' names have been engraved on the two curving, 304-foot-long blue-gray marble walls.

McCarthy and other Lindenwold officers will be at the ceremony.

Genavieve Foyle, 35, a great-granddaughter of Shannon's; her 9-year-old daughter; and other family will be, too.

"He wasn't forgotten," said Foyle, who lives in Clementon and has put together a family tree online.

Shannon served in the Spanish-American War. He worked as a constable in Clementon before that township was broken up to create smaller boroughs and was one of the first regular policemen in the department in Lindenwold, which was incorporated in 1929.

Officers patrolled mostly on foot and bicycle, according to a history of Lindenwold by Charles W. Shaylor.

By 1946, Shannon was a widower with eight surviving adult children, Foyle said. Her grandmother, Cecilia, was the youngest of the eight, whom Shannon adored and kept a close watch over, said 92-year-old Anne Gilbert, Cecilia's childhood friend.

Gilbert remembered how Shannon bought Cecilia a flowing gown when the girls joined a youth choir at St. Lawrence Church on the Pike, near Linden Avenue.

"As far as she was concerned, he would spare nothing for her," Gilbert said.

Shannon had moved in with Cecilia, who was married and lived across the Pike from St. Lawrence. Cecilia was pregnant and had a toddler. Her husband was in Italy, stationed there in World War II, Gilbert said.

On Christmas Eve in 1946, Shannon was directing traffic for parishioners attending St. Lawrence's midnight Mass when 23-year-old Milton H. Goodwin, a serviceman from Clementon, struck Shannon and sped away, according to a report in the Camden Evening Courier.

By then, the White Horse Pike had already evolved from a footpath to a paved and lit multilane roadway, a major highway for commuters and vacationers between Philadelphia and Atlantic City, according to the book Images of America: The White Horse Pike by Jill Maser.

The impact hurled Shannon 125 feet, according to the news report.

Ceclia, 26 then, was looking out the window and saw her father hit, said Patricia Kelly, her oldest child, who turned 3 the next day.

"She lost her voice for three months," Kelly, 67, who lives in Conway, N.H., said.

State troopers and local police chased Goodwin's vehicle but lost it. Three days later, Goodwin confessed and was charged with manslaughter.

Cecilia's voice would return but she rarely spoke of that night, Kelly said.

One snowy night nearly a decade ago, James Valentine Jr., walked into a Holiday Inn in North Conway, N.H., where Kelly was working the front desk.

Valentine was a former fire chief, councilman and director of public safety in Lindenwold. At the time, he owned a fire investigation company and was in New Hampshire on business.

He recalled that his conversation with Kelly went along these lines:

"You're from New Jersey?" he said Kelly asked him.

"I'm from Lindenwold," he said.

"That's where I was born and raised," she said.

"You're kidding me," he said.

"My grandfather was a police officer. He was killed on the job," she told him.

The wheels started turning in Valentine's head. He had envisioned a monument for officers in town.

He told department officials of his discovery of Shannon, but nothing happened.

Then, two years ago, McCarthy found an old photograph of Shannon and a newspaper article in a box in the department, items Valentine had left.

McCarthy found more newspaper articles at the Camden County Historical Society.

He tried to get a police report but the state police records of that time were believed to have been destroyed.

An Evening Courier story mentioned that Shannon was pronounced dead at Audubon Emergency Hospital, which no longer existed.

McCarthy finally found a death certificate at Cooper University Hospital in Camden, where Shannon was pronounced dead.

He needed a family member and found Foyle on Ancestry.com, where she had a family tree.

In February, McCarthy learned that Shannon's name would be added to the memorial. "I knew it was going to take some time and I just planned to keep plugging along," he said this week.

Kelly said she was pleased that her grandfather, "a little forgotten guy, old Pop Shannon," was being remembered.

A few days ago, Foyle met McCarthy at the Lindenwold police station and gave him a card. It read: "Thank you for your diligent efforts in having my great-grandfather's memory honored."

It was signed: "From his grandchildren and great-grandchildren."