The Grandfather

It is the story (fictitious) of a grandfather who dies and when arriving in Heaven gets an interview with God where he asks to return to Earth in any form to be able of enjoying his grandchildren which he has been unable to enjoy because of his illness, while the other grandfather is enjoying them. God concedes and sends him back to earth converted into a bird, under certain conditions. The story tells the vicissitudes he has to endure on Earth, among people, other birds, etc. How he tries to get his purpose of enjoying his son and his grandchildren, including an escape to Spain.