One of the reunions that fans were expecting to see in Lord Commander of the Night's Watch.
But there was another side to Game of Thrones season 7 and season 8. Lyanna is currently the leader of House Mormont, who rule over Bear Island and have sworn fealty to House Stark. Lyanna's mother, Maege Mormont, was the previous Lady of House Mormont, and she sided with Robb Stark at the start of the War of the Five Kings. Sadly, she was killed fighting for the Starks, and that's why the responsibility of carrying on the Mormont name fell to Lyanna. The thing is, Lyanna isn't the only Mormont left alive.
As revealed (and made quite clear) in Game of Thrones season 8, episode 2, Jorah and Lyanna are cousins; Jeor and Maege Mormont were siblings. When Jeor voluntarily ed the Night's Watch, he relinquished all titles, including being the head of House Mormont. And so, Jorah became the new Lord of Bear Island. But since his future wife accumulated quite a bit of debt, Jorah resorted to selling poachers into slavery - an illegal act in the Seven Kingdoms. He was then stripped of his titles, and he fled to the Free Cities and eventually ed up with Daenerys Targaryen.
Because of what happened to Jorah, Maege Mormont became the Lady of Bear Island, and then when she died, Lyanna became the House's leader. Battle of Winterfell and perhaps later in the fight for the Iron Throne will be integral to House Mormont continuing on. Already so many Houses in Westeros have been destroyed in either the War of the Five Kings or in the war against the Army of the Dead.
If Jorah and Lyanna both die in the Battle of Winterfell, seeing as they're both more than willing to fight against the Night King and his Army of the Dead, then House Mormont will season 8 premiere. But, hopefully, at least one of them survives. They each have a role to play in the grander scheme of things, including defending the North and helping defeat Cersei, as well as taking back the Iron Throne. We'll just have to wait and see if either of them does live.
Game of Thrones season 8 airs Sundays at 9 pm ET on HBO.