Diplaying a pyramid structure from a database

Question

I need to create a database that can allow me to save a persons details, than that person can join two people under his name, and the two need to join 2 people, than the other 2 can join 2 people. This needs to form a hieracy in a way. Than if that person has 15 people under his name, can be moved to another table.

How do I go about creating that database, I have struggled for almost a week trying to think of a solution but nothing has crossed my mind. Any help would be appreciated.