Lyanna Mormont is my home girl
And yes, Sansa was 14 (there was a whole set of episodes where they had to figure out if she "flowered" yet...). Wiki's say Show!Sansa is 18. It's still creepy that the dude who loved her mom is in love with her... because he's still hung up on mom.
The only reason I think Jon+Daeny might not happen is he's so super focused on defending the North. Perhaps once the White Walker thread is dealt with?