In a worn path by eudora welty what part of the trip is especially difficult for phoenix?

Eudora Welty's ''A Worn Path,'' first published in Atlantic Monthly in February, 1941, is the tale of Phoenix Jackson's journey through the woods of Mississippi to the town of Natchez. The story won an O. Henry Prize the year it was published and later appeared in Welty's collection The Wide Net. Since then, it has been frequently anthologized. At first the story appears simple, but its mythic undertones and ambiguity gives a depth and richness that has been praised by critics. Welty has said that she was inspired to write the story after seeing an old African-American woman walking alone across the southern landscape. In "A Worn Path," the woman's trek is spurred by the need to obtain medicine for her ill grandson. Along the way, Phoenix encounters several obstacles and the story becomes a quest for her to overcome the trials she faces, which mirror her plight in society at large. The story is one of the best examples of Welty's writing, which is known for its realistic portrayal of the American South, particularly during the depression.

You can read the entire story here:
http://www.moonstar.com/~acpjr/Blackboard/Common/Stories/WornPath.html