LAWRENCE, Mass. – The younger sister of U.S. Marine Sgt. Johanny Rosario said died as she lived — helping others.

Rosario, 25, a supply chief whose goal was to become a social worker to protect children from abuse, was among members of the U.S. military screening Afghans fleeing the Taliban when a suicide bomb exploded outside the Abbey Gate at the main airport in Kabul on Thursday.

The attack killed 13 service members, including Rosario.

“We are all in denial. We just can’t grasp this,” her younger sister, Rosalidna Rosario, said during an interview Saturday. “I can’t grasp this … to have to receive our hero, our beautiful brave sister.”

On Thursday, three Marine staff sergeants came to the family’s home in this old mill city 25 miles north of Boston to inform them that Johanny had been killed.

On Saturday, Rosalinda and her mother, Colassa Rosario, flew to Delaware so they could meet her body at an Air Force Base when it returned to U.S. soil.

Rosalinda said her sister was someone who was “always nice to everybody” and willing to lend emotional support, advice or a hand when necessary.

She described her as beautiful, driven, focused and always striving to accomplish more.

“She was just the best person. She was my hero, the hero of Lawrence, a hero who died helping people,” she said.

Johanny Rosario graduated Lawrence High School’s math, science and technology school in 2014 and enlisted in the Marine Corps. Her sister said she was working to earn her bachelor’s degree.

“She was very smart — the smartest person in our family,” she said.

Johanny’s death comes at a difficult time for the Rosario family, who face eviction from their apartment. Her sister said they’ve been trying to find a three-bedroom apartment and a landlord who accepts Section 8 payments.

On Saturday, Jonathan Guzman, a member of the Lawrence School Committee and former classmate of Rosario’s, described the pain of her death in a social media post: “It hurts to see a classmate, a friend, an LHS (alumna), a young lady, a proud Lawrencian, a wonderful person with a kind heart taken from this world by the hands of hatred. Your city will honor you. That is a promise.”

Rosario’s sister said she’d been moved to work with children in need after watching a Netflix docu-series on Gabriel Fernandez, an 8-year-old California boy murdered in 2013 after being tortured by his mother and her boyfriend.

“She said, ‘I never want to see a kid go through that again,’” she said.

Rosario served in the 5th Marine Expeditionary Brigade’s Task Force 51. A military social media post in May lauded her work as a supply chief who handled administrative functions including procurement and accounting of unit equipment.

She had a boyfriend, according to her sister. “The love was still there,” she said. “It was just the distance.”

Rosario had also adopted a rescue dog, named Lena, which her sister now hopes to bring back to Lawrence, noting it and some messages are all she has left.

“I wish I could talk to her one last time,” she said.