How did melisandre know to say you know nothing Jon Snow?

Related questions

1. Was ygritte a virgin?
2. Why the Night's Watch killed Jon Snow?
3. Did they burn ygritte?
4. Is ygritte in the books?
5. How did ygritte die in the book?
6. Why was Jon Snow labeled a traitor?
7. Is ygritte related to Tormund?

Tags

1. #doesn
2. #stunned
3. #foolish
4. #saviour
5. #uttered
6. #nothing
7. #everybody
8. #melisandre
9. #resurrect
10. #lover
11. #beautiful
12. #lovingly
13. #leslie
14. #those
15. #ygritte
16. #words