In the given passage from the book "The Absolutely True Diary of a Part-Time Indian" by Sherman Alexie, the cultural belief of staying together as a family within the Spokane Indian Reservation significantly impacts Junior's perspective.
What happened in the story
His family has historically adhered to the tradition of not leaving one another. However, with Junior's enrollment at a new school and his sister's sudden marriage leading to her moving away, this cultural practice is challenged.
For the first time, members of Junior's family have ventured outside the reservation. This experience challenges Junior's perspective by exposing him to the possibility of a life beyond the reservation, highlighting both the sense of loss and the potential for personal growth and new experiences outside their traditional community.