Game of thrones fan theory about the white walkers intent.
In short I believe family is a big part of the saga and the only reasonable thought I have for the white walkers coming to destroy everyone is revenge. Revenge is a big part of the saga also so my belief is in the first battle the white walker leader was killed but his son was still alive growing up in the far north.
The son has gathered his army and waiting for the return of dragons and with his own green sight ( like bran) has seen the actions happening in the world.
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