The Countess of Foix was the sister of the King of Navarre, and between the Count her husband, and the King her brother, a quarrel arose on a question of money. The Count therefore sent his wife to her brother at Pampeluna, that she might arrange the matter; but the end of it was that she stayed in Navarre, and did not return to her lord. Meanwhile her son Gaston grew up at Orthez, and married a daughter of the Count of Armagnac, being now a lad of sixteen, a good squire, and in all things very like his father. He had a desire to see his mother, and so rode into Navarre, hoping to bring home his mother, the Countess of Foix. But she would not leave Navarre for all that he could say, and the day came when he and the young squires of his company must return. Then the King of Navarre led him apart into a secret chamber, and there gave him a little purse. Now the purse was full of a powder of such sort that no living creature could taste of it and live, but must die without remedy.
'Gaston, fair nephew,' said the King, 'you see how your father, the Count, holds your mother in bitter hate--a sore grief to me and to you also. Now to change all this, and bring your father and mother back to their ancient love, you must watch your chance and sprinkle a little of this powder on any food that your father is about to eat, taking good care that no man sees you. And the powder is a charm so strong that your father, as soon as he has tasted it, will desire nothing so much as to be friends with your mother again, and never will they leave each other. But you must take heed that no man knows of this purpose, or all is lost.'
The young Count, believing, in his innocence, what his uncle said, made answer that he would gladly do as he was bidden. Then he rode back to Orthez, and showed his father all the presents and jewels that had been given to him in Navarre, except the little purse.
Now it was the custom of the young Count to be much in the company of his brother by another mother, and, as they played together one day, this boy, named Yvain, caught hold of the little purse which Gaston wore about his neck under his coat, and asked him what it was. But Gaston made no answer. Three days later the lads quarrelled over a stroke at tennis, and Gaston struck Yvain a blow. Yvain ran weeping to his father, the Count, who asked what ailed him.