How is Cal, Rachel's younger brother, described in the novel, Words in Deep Blue?

Cal was tall and skinny, described as looking like a dandelion wearing classes. He was dorky, but likeable, and quiet at school but interesting when you got to know him. He was always fascinated by science and the ocean, as Rachel was. However, rather than looking for empirical facts and data, he loved the possibility that was present in science. He liked to think about the potential methods of time travel, or whether or not supernatural entities were present in the universe.