BALTIMORE (WJZ) — A mentor who threw himself into his job. A sister who lived her life to the fullest. An optimist who was hopeful even in tough times. Those were some of the ways loved ones remembered three fallen Baltimore firefighters.

The families and friends of Lt. Paul Butrim, Lt. Kelsey Sadler and Kenny Lacayo were among thousands of mourners who gathered Wednesday morning at the Baltimore Convention Center to pay their respects to the trio of firefighters who were caught in a building collapse last week while fighting a fire in West Baltimore.

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Speaking to those in attendance, Baltimore City Fire Chief Niles Ford said losing one member of the fire department was a “terrible tragedy” on its own. But he said losing three members of his department is “almost unbearable.”

“They have lived a committed life of service. They loved people, and they served humanity,” Chief Ford said. “Their lives were not in vain.”

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Butrim, Sadler and Lacayo died in the line of duty on Jan. 24 after a vacant home partially collapsed while they were inside, trapping them underneath the rubble. A fourth firefighter, John McMaster, has since been released from the hospital.

Their deaths galvanized the Baltimore community, leading Mayor Brandon Scott to order a city-wide review of what is being done to bring the city’s vacancy problem under control, and sparking a criminal investigation into who started the fire.

“Each of them has made the ultimate sacrifice for us,” Scott said. “We all owe them our deepest sense of gratitude, honor and respect—not just today and not just tomorrow, but forever.”

Yet rather than dwelling on the tragedy, mourners spent Wednesday’s memorial remembering the lives of three firefighters who made a living throwing themselves into harm’s way to save others’ lives—and paid the ultimate price.

Lt. Paul Butrim

Battalion Chief Joshua Fannon remembered Butrim as a firefighter who threw himself into every detail of the job and became a mentor to younger members.

“He took them under his wing and taught them every aspect of fire service life, whether we’re talking tricks of the trade, conducting effective search and rescues, ventilation techniques and much more,” Fannon said.

Fannon recalled the time Butrim was honored by Firehouse magazine in 2015 after he located a child face down in an apartment fire and performed CPR until emergency medical services arrived.

After Butrim was promoted to lieutenant in 2016, “he made sure firefighters assigned to him were always working on learning the fine points of the job and bettering themselves by drilling on every aspect,” Fannon said.

Fannon also remembered Butrim’s sense of humor, saying he had a dry wit and often kept a straight face until other people in the conversation started to catch on.

“Once he saw you smiling, he would burst out laughing,” he remembered.

Butrim, 37, was a fan of the Boston Red Sox, Washington Capitals, but his biggest love was NASCAR, Fannon said.

Fannon said Butrim was a staple at races at Dover Motor Speedway.

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“[H]is best friend to take was certainly his son Nolan,” who died three years ago this month, he said.

Butrim will be buried near his son.

“(Paul) was born to be a father, and he and Nolan were inseparable,” Fannon said.

Lt. Kelsey Sadler

Sadler’s sister, Lacey Marino, said her sibling would have hated all the attention she got at the memorial, recalling the time she was upset by a surprise birthday party.

Marino remembered Sadler as a confident, creative and supportive person who lived life to the fullest.

“Kelsey loved life, and she lived it like she meant it, all gas and no brakes,” she said. “She was always up for any task or challenge.”

Sadler, 33, was posthumously promoted to lieutenant following the tragedy.

Marino remembered talking with Sadler on the phone after a shift and hearing her say her fire company had eight calls after midnight.

“She was just a boss, she was awesome,” said Marino.

Even though Sadler had said she never wanted to have children, Marino called her an excellent step-mom and “the coolest aunt.”

Marino asked her daughter about her favorite thing to do with Aunt Kelsey, and the girl replied, “Everything.”

Firefighter Kenny Lacayo

Lacayo, 30, was remembered as a music lover who traveled all over to attend concerts.

His fiancee, Clara Fenelon, said, “I recently told him, I could not believe that life had done a full spin, and somehow I end up on top. I was on top of the world with my Kenny.”

Fenelon said she took solace knowing most people spend their entire lives looking for the love she and Lacayo had. She hasn’t been back to their home and looked at the laptop that still has their wedding guest list on it.

“I know this loss will forever change who I am,” she said. “But loving and sharing a home with you, my Kenny, has been the biggest honor of my life, and I would not change a thing.”

Lacayo’s sister, Kattia Elizabeth Olivas-King, said her brother loved his family and being a firefighter. After falling in love with Fenelon, “he finally found the one piece he was missing to help him feel complete,” she said.

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And while the public now thinks of Lacayo as a hero, she said she will remember him as “sweet and gentle and kind and always optimistic, even in the darkest moments.”

Ava-joye Burnett