Lyanna's cool and all, but Lady Mormont? Fuck off. She's the one Mormont in the books who doesn't pledge themselves to Stannis. She mouths off like the little girl that she is while the actual controllers of her house pledge themselves.
Just another slight to Stannis.
Your lordship lost a son at the Red Wedding. I lost four upon the Blackwater. And why? Because the Lannisters stole the throne. Go to King’s Landing and look on Tommen with your own eyes, if you doubt me. A blind man could see it. What does Stannis offer you? Vengeance. Vengeance for my sons and yours, for your husbands and your fathers and your brothers. Vengeance for your murdered lord, your murdered king, your butchered princes. Vengeance!