Lyrah and Caleb have a condition in common. There is a dangerous and expensive treatment. Caleb wants to pursue it, Lyrah wants to accept her fate. It's not as if it's the end of the world...yet.
A very short look at the other side of immortality.
Everyone is a perfect size for something.
Pillow wanted to have a purpose. He wanted to be useful to someone but he seemed to be too small -- just big enough for an ant’s head, and ants do not use pillows. So pillow watched others and learned to wait and grow until the day came when he was big enough to serve a very important purpose.