The sleet on Saturday morning seemed to hold the sadness of the hundreds of people who packed into Alexandria’s Blessed Sacrament Catholic Church for the funeral of 59-year-old Ruthanne Giammittorio Lodato, a beloved music teacher with longtime roots in the area who was killed Feb. 6 by someone who came to her door.

The unsolved slaying has left unease in the tight-knit community of neighbors and parishioners, many of them residents for generations. But they gathered to celebrate the decades of joy they said Lodato and her family had injected into their lives and into the fabric of the city.

“You couldn’t go anywhere without running into one of her students,” neighbor John Kelly told the mourners, who spilled into the vestibule. “She was a neighborhood institution.”

Lodato’s childhood friend Joan Gartlan, her voice breaking, recalled her as “one of those people in our lives who . . . don’t always get the recognition they deserve for their kindness, their hard work, their caregiving and their organizational skills, because they make it all seem so easy and they don’t ever seek out any recognition.”

The mother of three adult daughters, Lodato and her husband cared for her 89-year-old mother in their home on Ridge Road Drive across from the house Lodato had grown up in. A caregiver, who was in the Lodato home at the time of the slaying, was also shot and injured.

Lodato taught piano lessons for decades and was director of Music Together Alexandria, a music program for children. She also played piano and organ for her church and other places of worship.

Alexandria police have not made an arrest in the case. On Saturday, they said they had no updates. They have urged residents to lock their doors and windows and to not open their doors to strangers. Some wonder whether the killing is connected to other apparently random unsolved slayings in the city.

Many mourners stayed after the service to pay their respects to Lodato’s husband, Norman, and their daughters, Lucia Lodato, 32, Gina Lodato Pelusi, 29, and Carmen Lodato, 20. A photo display showed Lodato as a little girl, as a long-haired teenager, as a smiling, young bride. In later photos, she sat at a piano keyboard, alone or alongside one of the many children she taught.

Alice Rogalski, a friend and neighbor, recalled how Lodato helped her daughter prepare for a singing audition. “She gave her the confidence,” she said. Looking around the church, she added, “It’s just so odd, because at a funeral like this, you expect to see her there.”

Laura Casey, 32, a childhood friend of one of Lodato’s daughters, said she had been close to the family since fifth grade.

“They were like a second family for me. I just think of her as such a loving mother,” she said, adding that Lodato and her husband “wanted to know everything about anyone. They were very good at connecting on a personal level.”

Casey, who traveled from New York City to attend the service, recalled the large get-togethers where Lodato’s extended family would serve homemade pasta and play boccie. “They all grew up in that house. To have that kind of violation, it’s such a nightmare.”

Alexandria Sheriff Dana A. Lawhorne, a longtime friend who attended the service in uniform, said that Lodato and her husband “epitomize family.”

“A long, loving marriage, and very faithful to each other, very faithful to their children, to their siblings,” Lawhorne said. Now, he said, the family is “in shock, they’re just numb.”

Hearing that there had been a shooting, Lawhorne said, “To be honest, when I saw that it was her, my immediate sense was just, ‘This wonderful woman never hurt a flea or had an enemy in the world. Why would someone take her life?’ ”

That question has haunted many Alexandria residents in recent days, and it has eroded their sense of security.

“My long-term law partner is used to dropping by at any time and coming in,” said Hugh Nugent, a friend, neighbor and fellow parishioner of the Lodatos. “He dropped by last night, and he couldn’t get in, because we locked the door.”