The Cat on the Dovrefjell (also known as The Cat on the Dovre-Mountain and The Trolls and the Pussycat) is a Norwegian fairy tale collected by Peter Christen Asbjørnsen and Jørgen Moe in Norske Folkeeventyr.
[2] A man was bringing a white bear to give to the king of Denmark, and he came to the mountain Dovre on Christmas Eve and asked a man called Halvor for shelter for the night.
Halvor told him that trolls came to every Christmas Eve and made such havoc that the household had to flee them.
The trolls came, eating the feast the people had left behind, and one began to bait the bear, calling it "Kitty".
Jan Brett retold this story as Who's That Knocking on Christmas Eve, featuring a boy as the bear's owner and a girl as the one who welcomed him.