Somebody had a serious glow-up.
The final episode of Game of Thrones Season 8 saw the conclusion of years of stories spread across dozens of characters. Things ended tragically for some characters while others came out pretty well, all things considered. The series finale, entitled "The Iron Throne," also saw the return of a few characters who've been missing from the show for a while, updating viewers on their fates. There's one person in particular, a young man, who you may not remember--but he's looking a whole lot different these days.
A word of warning: there are spoilers for Game of Thrones Season 8, Episode 6, beyond this point!
After Daenerys Targaryen's sack of King's Landing, Tyrion Lannister tries to convince Jon Snow that something has to be done about the queen. Jon is finally convinced and when he finds himself alone with Dany, he pledges his loyalty to her one last time--before stabbing her with a dagger, killing her.
Without a monarch to lead the Seven Kingdoms, the surviving lords and ladies of Westeros meet at the dragon pit in King's Landing to decide who should rule. There are a lot of familiar faces in attendance, including Yara Greyjoy of the Iron Islands, Edmure Tully of Riverrun, Ser Davos, Ser Brienne of Tarth, and Yohn Royce, who led the Knights of the Vale in the Battle of the Bastards. You might have caught sight of another familiar face with Lord Royce: the grown-up Robin Arryn, Lord of the Vale.
We first met Robin in Season 1 when Catelyn Stark took the captured Tyrion Lannister to the Eyrie to get the help of her sister, Lysa Arryn. Robin was the son of Lysa and Jon Arryn, the former Hand of the King who died before the start of the series. With his father's death, the young boy became the new Lord of the Vale. When Robin first appeared on the show, his mother was breastfeeding him (despite the fact that he was definitely about eight or 10 years old at the time). He went on to demonstrate how spoiled and awful he was as he demanded that Tyrion be tossed out the Moon Door.
Robin showed up again in Season 4, when Littlefinger brought Sansa Stark to the Eyrie after spiriting her away from King's Landing in the wake of Joffrey Baratheon's death. At that point, he was still spoiled and awful--you might remember the temper tantrum he threw while talking to Sansa, stomping on her snow castle.
According to Lysa, the plan was that Robin was to marry Sansa, but that obviously never happened. Littlefinger threw Lysa out the Moon Door instead, and eventually, he married Sansa to Ramsay Bolton. We last saw Robin in Season 6, being absolutely miserable with a sword. That was when Littlefinger sent Robin to live with Lord Royce, who was charged with training the young lord and turning him into a man.
Who knows if Robin ever learned anything, but he's definitely come a long way since Season 6. At the council meeting, we see an adult Robin (actor Lino Facioli, who plays Robin, is 18) who looks a lot less sickly than he did as a kid. One wonders if Sansa thinks she made a mistake bailing on Robin; then again, it's hard to separate the good-looking young man from the way-too-old-to-be-breastfeeding boy.