Puberty is a time when your body begins to change. The average age when a boy’s body begins to mature is usually around age 10 or 11, but can range from 9-13. During this time you will probably notice that both your penis and testicles (balls) get bigger. You will also grow taller. During puberty your body begins to make sperm. Sperm are found in semen, which is what comes out of your penis when you have a wet dream. There is no exact age when wet dreams start. It is just some time during puberty. It’s normal to have wet dreams, but it is also normal if you don’t.
Read more about wet dreams: https://youngmenshealthsite.org/guides/wet-dreams/