Sarah J. Maas said this quote

The stag’s enormous head turned slightly—toward the wagon, toward the small window.The Lord of the North.So the people of Terrasen will always know how to find their way home, she’d once told Ansel as they lay under a blanket of stars and traced the constellation of the stag. So they can look up at the sky, no matter where they are, and know Terrasen is forever with them.