In "Hills Like White Elephants" how does the story of Buddha's mother's dreaming of a beautiful white elephant establish the symbol of white elephants?

Buddhist folklore:

According to Buddhist folklore, Queen Maha Maya, the mother of Buddha, dreamed of a white elephant holding a lotus flower when she became pregnant with the Buddha. King Suddhodana, Maya's husband, consulted priests to learn the meaning of this dream. According to their interpretation, Queen Maha Maya would give birth to a child who would become a great ruler or a Buddha. By alluding to this story, Hemingway introduces the idea that the pregnancy—or white elephant—can be seen as sacred and beautiful.

The girl is more enlightened than the American. She sees what is special in her baby while the man interprets the baby as a problem to be gotten rid of.