Anxiety and the Chills - The Cause and Connection. The idea is that the anxiety of the horror movie provides a level of fear that sends chills down your spine. Anxiety has often had a connection to chills, even though the exact relationship between anxiety and these chills often seems so unclear.
No one knows for sure. The popular theory is that the Night's King is indeed a Stark. That he was the Lord Commander of the Night's Watch who lived during the Age of Heroes, 8000 years before the time of the series. It's believed he fell in love with a female White Walker, fell in love with her and that they mated.
Is it because Bran can warg and time travel? Does the White Walker not even care about Bran and just wanted to destroy the Three-Eyed Raven and the Children of the Forest? Is Bran just a bonus in the Night King's endless path of destruction? It's hard to tell, but one fan theory may provide an explanation.