Anne and Peter have opposing views regarding the Star of David, in addition Anne is really social and likes to make friends, however Peter is the opposite, he describes himself as a lonewolf and doesn't show any interest when talking to Anne. The author highlights those differences because they would live together for a while even though they are different, it would be convenient for them to get along.
Anne is outgoing, talkative, and sensitive. She always remains optimistic about her family's situation throughout their ordeal. Peter is quiet and rarely expresses his personal thoughts and feelings. Anne sees herself as accomplishing something great in life, while Peter says he wants to be a gambler or just loaf around. Anne spends some of her time studying, while Peter sees his studies as a boring requirement. Anne is reflective about her strengths and weaknesses while being self-confident about what kind of woman she wants to become. Peter obviously has not given that much thought to his future.
The author wanted to show these differences because it reveals that they don't really fit each other's personality very well and they can't really relate to a lot of things, but they love each other.
I Believe the answer is: Serial position effect Serial position effect refers to a tendency among people to held the first and lest object of memory in higher regards compared to the one that placed in the middle. This happen because most people use the first and last objects in the list to mark and separate one set of memory with another.<span />