Wet dreams, also known as nocturnal emissions, are a normal part of puberty for boys and can occur during sleep when a boy ejaculates spontaneously without manual stimulation. Wet dreams usually begin during puberty when the body starts making more testosterone, a male hormone, and are a sign that a boys body is preparing for the day in the future when he might decide to be a father. Most boys have wet dreams at some point during puberty, and even sometimes as adults. Wet dreams typically start between ages 13 and 17, with the average at around age 14.