War is inevitable in the "Game of Thrones" Season 7. With Lyanna Mormont's pragmatic character, it would be difficult to assume where her loyalty lies. Yes, she had shown her support to Jon Snow, portrayed by Kit Harington, and Sansa Stark, by Sophie Turner in the previous season but then she's 10 years old! Her allegiance could very well shift with the turn of events.
The war against Ramsay, portrayed by Iwan Rheon, put Jon Snow in charge of Winterfell, and as King of the North. That has been the agenda of Lyanna Mormont: to put the Starks where they rightfully belong. It is the same agenda for uniting the North. But if war breaks in "Games of Throne" Season 7, which side will the Lady takes on?
Jon Snow and Sansa Stark will definitely have a new adversary in the next season. Who will it be? They could plan to throw Cersei, portrayed by Lena Headey, from the Iron Throne and cause a revolution. They could seize on the Night King or they could hold our their forces against Daenerys' unevitable invasion. Whatever they plan to do, war is definitely brewing in 'Game of Thrones" Season 7.
If Jon Snow decides to fight the White Walkers in "Game of Thrones" Season 7, Lyanna Mormont might be ready to take sides with him. After all, the White Walkers are definitely dangerous to her homeland. But if Jon Snow takes a fight over the Iron Throne, she might not just be up to it as she has already claimed to disown the throne.
In "Game of Thrones" Season 7, Sansa Stark could team up with Jon Snow. Or she could also be the next villain and betray her own brother? Sophie Turner said that her character might just run off with Littlefinger, after all. As the series is famous for killing its star characters, it will not be a surprise to see Sansa Stark put to death in the next season.