Carolyn Collins, a high school custodian in Tucker, Ga., was about to take out the trash in the early morning darkness when she heard a loud knock on the cafeteria door.

She set down her garbage can and cracked the door. Two students — a boy and a girl — looked at her nervously. "Can we please come in?" the boy asked. School didn't start for two more hours. "Me and my sister are getting tired of waiting outside."

They said they'd been living in a car with their mother, who had dropped them off early so they could get ready for school in one of the restrooms. Collins felt her eyes fill with hot tears. The teens were hungry, so she hustled up some fruit, milk and cereal.

That was four years ago, the day she hatched a plan for a school "care closet" — food, clothing, shoes, toothpaste, shampoo, deodorant and more — all free to any student at her school, Tucker High, about 25 miles from Atlanta.

"I knew that they weren't the only kids at school who were struggling," Collins, 54, told the Washington Post. "And I thought, 'I'm going to do whatever I can to help these kids. High school is hard enough without being homeless.' "

Hours after she let in the homeless siblings, Collins stopped at several dollar stores after work on her 6-mile drive home. She spent $200 on snacks, toiletries, socks, underwear, notebooks and pencils, and then stopped by the principal's office the next morning to let administrators know she planned to help students in need and hoped they would provide her with space.

Later that day, Collins' care closet was up and running in an old storage room near the cafeteria.

Since 2014, any of the school's 1,800 students who are in need of items such as food, soap, school supplies, book bags, clothes — even prom wear — will quietly mention it to Collins and she'll open the closet. They can take what they need.

"She has such a giving heart. She's a beacon of light for every kid in need," said Principal Eric Parker.

"I love her with all my heart, she was my angel," said Kennedy Carroll, 21, a Tucker High graduate who is now a sophomore at Savannah State University. He once lived in his mother's car for several months until a classmate's family took him in.

"Ms. Collins took me aside a couple of times and made sure that I was doing OK and asked me what I needed," said Carroll. "And I basically told her, 'everything.' I didn't have clothes or good shoes or food, or even a toothbrush. She gave me all of that and more."

Between her duties of mopping, sweeping and polishing, Collins said she always makes time to stock the closet and reach out to students. There is another, more painful, reason for her dedication.

Six years ago, one week before Thanksgiving, her grown son was in the wrong place at the wrong time and was killed during a home invasion robbery. She and her husband miss him every day.

"I want to give kids what they need so that nobody has to go out and steal from anyone," said Collins, who has worked at the school for eight years. "I don't want any other parent to have to go through what I did and lose a child at a young age for no reason."

She is always on the lookout for teens wearing the same clothes, shuffling through the halls with their heads down — a sign that they might be homeless or experiencing other stress.

Students such as Carroll who return later to say "thank you" make the long days of scrubbing toilets and emptying trash cans worthwhile, said Collins, who dreams of opening similar closets in other high schools.

"When I tell them, 'I love you,' and I see the smiles on their faces, that's pure joy," she said. "Everybody needs somebody. Seeing that they know they are loved, that's my reward."