After the student had studied the Vedas, he could come home again to get married. From that time, one was expected to pursue children. For those in this stage, texts like the Kāma Sūtra explained sexual life.
The practice of a young person leaving home to study with a religious guru is seemingly echoed in popular Buddhist practice in Theravada Buddhist countries.
In those Buddhist societies, a young man will traditionally become a monk for a short time to gain knowledge of spiritual texts and practices before he can return home to marry.