Twelve years after 9/11, fallen FDNY Lt. Jeffrey Walz has finally come home to his family.

Authorities yesterday identified the remains of Walz, the son of a retired city firefighter and a married 37-year-old dad who worked out of the East Village.

“My family always felt at some point we would get a phone call,” Walz’s widow, Rani, 50, told The Post. “I wasn’t so sure. This has reopened old wounds.”

Jeffrey Walz’s remains were among debris recovered from Ground Zero in the initial aftermath of the terror attacks on the World Trade Center, where a total of 2,753 perished, officials said.

But his remains were only positively identified as better DNA-testing techniques became available to city investigators.

Walz’s sister, Karen Ciacco, said yesterday, “I’m happy we got the phone call.

“It’s a little bit of a shock, but it was something that I felt would come about,’’ she said. “We always felt that we would get something from him. I felt as though he came home to the family.”

Still, “it’s brought up a lot of old feelings,’’ the sibling added. “It’s a constant reminder of that day. It was a horrible day for thousands of people.”

Ellen Borakove, a spokeswoman for the city’s Medical Examiner’s Office, said the remains of 1,637 WTC victims have been identified so far, while those from 1,116 others who died have not.

The last previous identification of a 9/11 victim occurred June 20, after the ME’s Office retested the remains of a 43-year-old woman. Her name was not released in accordance with her family’s wishes.

On the morning of 9/11, Walz, a Staten Island native, responded with his engine company, Ladder 9, to the World Trade Center.

While some of his comrades escaped the north tower, Walz was killed when the building collapsed.

“I first saw it on the news. We didn’t get any phone calls during the day from him,” Ciacco said.

“He did make two phone calls: one to his wife and one to his parents,’’ she said. “I never had the opportunity to talk to him.”

She said the last time she saw her brother alive was when they went to the Crayola Factory in Pennsylvania two days before 9/11.

“It was a great day. The kids were together. We were together. I remember every moment of that day, and I treasure it,” she said.

Walz’s widow, Rani, said her late husband was known as a “gentle giant.”

“My sister-in-law gave him the nickname,” Rani said. “It was obviously because of his height and because he was such a good person. He was very patient with everyone. He was a saint with me.”