It has become a daily routine for the students on bus No. 7 in Arlington, Washington, to wave to the "grandma in the window."
Every day for the past five years, you could find 93-year-old Louise Edlen sitting at her dining room table as the busload of schoolkids passed by.
But one day in early October she wasn't in her usual spot, NBC affiliate KING 5 reported.
After a few days of not seeing their old pal, the kids got worried. Eventually, they learned she had suffered a stroke.
"It was kind of heartbreaking because she was always there," seventh-grader Axtin Bandewerfhorst told the station.
But she was apparently still thinking about the 90 boys and girls who zipped past her home every day.
The day after bus driver Carol Mitzelfeld brought Edlen a bouquet of flowers, the kids looked out the window to find a sign reading, "Thank You."
"That made me really smile," 10th-grader Cheyanne Holt said. "It shows how much we mean to her."
So to welcome Edlen home from the hospital, they made her a sign of their own: a photo of the kids waving from inside the bus, the station reported.
"Carol was telling us that a lot of times she doesn't remember her daughter's name, but she always remembers to wave to the kids on the bus," Bandewerfhorst said.
"That made me feel really special."
Louise’s husband of 53 years, Dave Elden, with whom she has 30 grandchildren and 23 great-grandchildren, says the students' daily gesture “means the world” to his wife.
"It gives her something to look forward to every day,” he told KING 5.
Meanwhile, Elden has returned home, and is back to waving to the students every day.