Mariana Walker, a 69-year-old music teacher, passed away from cancer soon after her students sang to her outside her Alvin, Texas, home on Oct. 5 (video below).
Walker, who taught at Alvin Junior High School, was released from hospice care on Oct. 2. That's when Cindi Lee Cooper-Fields, a parent of a student, came up with the idea.
"I said, 'I think it would be beautiful if you all would sing to her one last time,'" Cooper-Fields told ABC News. "We knew that Mrs. Walker had cancer, but she never told the kids how bad it was. They knew that she wouldn't live much longer."
About 30 to 40 teens stood outside Walker's window and sang Hillsong United's "Oceans." Only 12 minutes after the students said their good-byes, Cooper-Fields received a text that Walker had passed away.
"[Her family] opened the doors so she could hear them sing," Cooper-Fields told KTRK. "It was one of the most beautiful gestures I have ever seen. Friends from all ages got together and sang like angels in hopes of her feeling our love and respect we all have for her."
Cooper-Fields' daughter Denim Fields recalled her teacher to KHOU: "She touched our hearts and she was someone you could trust. She loved us and we loved her unconditionally. She would take the shirt off her back for you at any time."
"She was a very special teacher to us," added Holly Darnell, another student. "She was more than just a teacher."
"She just really influenced me in all aspects of life, not just singing," junior Madi Webb told ABC News. "It was really hard for me because when I was in school there, I was really close with her. That was my last time really being with her."
Denim, Webb and other choir students were scheduled to sing at Walker's funeral service on Oct. 10 at a local church.