From THE WITCHES by Roald Dahl

"There was a family called Christiansen. They lived up on Holmenkollen, and they had an old oil-painting in the living room which they were very proud of. The painting showed some ducks in the yard outside a farmhouse. There were no people in the painting, just a flock of ducks on a grassy farmyard and the farmhouse in the background. It was a large painting and rather pretty.

Well, one day their daughter Solveg came home from school eating an apple. She said a nice lady had given it to her on the street. The next morning little Solveg was not in her bed. The parents searched everywhere, but they couldn't find her. Then all of a sudden her father shouted, 'There she is! That's Solveg feeding the ducks!' He was pointing at the oil-painting, and sure enough Solveg was in it. She was standing in the farmyard in the act of throwing bread to the ducks out of a basket. The father rushed up to the painting and touched her. But that didn't help. She was simply a part of the painting, just a picture painted on the canvas....And the peculiar thing was that little Solveg kept changing her position in the picture. One day she would actually be inside the farmhouse and you could see her face looking out of the window. Another day she would be far over to the left with a duck in her arms...she was always motionless, just a figure painted in oils. It was all very odd...Very odd indeed. And what was most odd of all was as the years went by, she kept growing older in the picture. In ten years, the small girl had become a young woman. In thirty years, she was middle-aged. Then all at once, fifty-four years after it all happened, she disappeared from the picture altogether." [Video]