Grandma Timeline & Summary

Grandma writes Oskar a long letter about her life, dated 12 September 2003.
She talks about growing up in Dresden with her sister Anna, and losing her whole family when the city was bombed.
She moved to New York by herself, where she ends up meeting Thomas, who was in love with Anna.
They decide to marry, but not have kids.
Then Grandma changes her mind and gets pregnant.
Thomas leaves her and goes back to Germany.
Years later, on September 11, 2001, the day Thomas Jr. dies, Thomas Sr. returns and moves in with Grandma.
She doesn't reveal his true identity to her grandson Oskar, only calling him "the renter."
After Grandpa digs up Thomas's empty grave, he decides to abandon her again.
This time, she follows him to the airport and decides to live with him there. At the airport. Really.