DEAR DOCTOR K: My son is 14, and his voice has started to change. Why does this happen?
DEAR READER: Your son is going through puberty. A change in his voice is just one of several changes in this phase of life. The first thing that generally happens to a boy during puberty is that his testicles begin to get larger and to make testosterone. Then, the penis begins to grow and sexual hair begins to appear. He will become more muscular. He will have more frequent erections, become capable of making sperm and thus become fertile.