Mystery Aeppli artist

Email inquiry: "I am searching for an artist called Aeppli. He painted anthroposovian pictures. Was it maybe the father of your grandmother who was teacher at the Rudolf Steiner School in Basel ? An oncle of my father was a teacher as well and bought a picture of an Artist called Aeppli.

I live in Aarau, about twenty kilometers away from Zofingen. The picture belongs to my father, and he told me to do researches about the Artist Aeppli. The picture is called «die heilige Nacht » it is a large triptychon. There are Angels on it."