GREEN-WOOD CEMETERY, Brooklyn (PIX11) -- He was a detective killed in the line of duty, but he was never given a proper burial. That changed on Monday morning, with a high honors funeral in Brooklyn for Detective Sgt. Bernardino Grottano, 100 years after he lost his life.

The funeral, and the process of planning it, also transformed some strangers into family -- quite literally. Grottano's long-delayed funeral united relatives in the police force who would have been otherwise unknown to each other. 

Inside the cemetery, under a blue sky, there were rows of blue uniforms, including some with top brass. There were also relatives of Grottano from as far away as Michigan, as well as an honor guard, highly-decorated veteran officers, and even canine officers. 

They all come together to pay tribute to a fallen hero.

"He got involved," said Paul DiGiacomo, the president of the detectives' union, in a eulogy, "to help another police officer." 

The Detectives' Endowment Association president was referring to the fact that Grottano seized a robbery suspect who was fleeing from an officer in Brooklyn on May 19, 1924. When Grottano grabbed the man, the man shot him. The detective died days later and was buried in a mass grave inside Green-Wood. All that marked his final resting place was a small, numbered stone marker. 

He'd had no funeral.  

"It was an unmarked grave," said William Markowski, the fiancé of Detective Grottano's closest living relative, his great-niece Phyllis Kropacek.

Markowski said that he'd searched Ancestry.com and other genealogical aids online to find the detective's final resting place, as well as details about Grottano's biography, and more. 

"We honor him finally," said Markowski, "and now we open the door to all these new relatives and stuff, that never knew each other."

He was referring to a sight in the front row at the graveside funeral service. There, two police officers -- one with Grottano's last name, the other with a grandmother whose maiden name was Grottano -- sat side by side. 

"It's just crazy," one of them, Officer Robert Desena, said, in an interview after the ceremony. "If you think about a hundred years ago, and to now be wearing the same uniform as well" as his new-found cousin, he said, was remarkable. 

That cousin is Officer Dylan Grottano, a two-year NYPD veteran.

It was through online messages among relatives leading up to Monday's burial that the two officers found each other. Desena, a six-year veteran in the evidence collection unit, and Grottano, a patrol officer in the 66th Precinct, met at their great-great uncle's funeral service. 

"If it wasn't for this," said Officer Grottano, "I wouldn't know I had another family member on the job, as well."

"We could've walked right by each other," he continued, "and never have known."

Kropacek, the great-niece of Detective Grottano, said that the officers' reunion, as well as the full tribute and new headstone for her loved one, turned a somber occasion into one that was more sweet than bitter. 

"Overall, there's mixed feeling," she said. "But I'm happy about the celebration."

"The day finally came," she continued. "A happy day."