Warfhuizen is known worldwide for this devotion, which is unique for the Groninger shrine. In Warfhuizen, Mary holds a large white handkerchief to dry her tears with. When coming to Warfhuizen, pilgrims bring a new one for her, often on behalf of someone who is ill or who is facing a difficult task. They give this handkerchief to the brother or the sacristan of the confraternity, who places the new handkerchief in the hands of Mary. The pilgrim is given the old one to take home, to give to the person concerned.
So when you see a large white handkerchief hanging over a hospital bed, you know what it’s about. And no, those students who are pouring over their exams do not all suffer from a heavy cold. But they are likely Catholic (or at least their grannies are…)