Paragraph- Sent 1: Hannah Harvey was a ten year old that had many friends in school.
Sent  2: She lived in New York and enjoyed doing gymnastics and playing soccer.
Sent  3: One day, Hannah came home from school and her parents greeted her.
Sent  4: She knew that something was different by the expressions on their faces.
Sent  5: Even Jackson, Hannah's dog, was acting different.
Sent  6: Hannah asked why everyone was being so strange.
Sent  7: Hannah's father, who was known as Pop, explained to Hannah that his job was forcing him to move.
Sent  8: Hannah did not seem to think this was too big of a deal.
Sent  9: Then, Hannah's mother explained that they were moving to Kenya.
Sent  10: Kenya, she explained, was a place in Africa and life would be very different there.
Sent  11: As Hannah began to cry thinking about all of her friends at home, Hannah's mother calmed her with a gentle touch.
Sent  12: Jackson began howling as Hannah cried, but was also calmed by Hannah's mother.
Sent  13: Hannah spent the next two weeks visiting her friends and saying her goodbyes.
Sent  14: She did not know the next time she would be home.
Sent  15: She cried very hard when she said goodbye to her best friend, Susan.
Sent  16: Susan did not quite understand where Kenya was, but promised to visit Hannah.
Sent  17: The next day, Hannah boarded a plane with her family.
Sent  18: At first, they thought that Jackson could not come with them.
Sent  19: However, Hannah worked hard and helped make sure that he had all of his shots so that he could come.
Sent  20: After he had them all, the airport said it was OK for Jackson to come!
Sent  21: The Harvey family left and off they went across the ocean to begin their new life in Kenya.? 
Question: If Susan is Hannah's best friend, why would she need to visit her?
No.