Before reading this I saw a lot of comments saying that there was a child who was Mikasa´s grandson, and that he was going to bring back de titans. But I don´t think the time is right. I mean, 7 pages and they show us that mikasa had a life, and die at an advance age, sure she had a son or whatever. But the important matter here is that Eren´s grave became kind of a sacred place. The tree is bounded, and separated from the streets. Time pases, the city changes, the civilizations advance, then there are wars(with a lot of technology). The tree keeps growing up, obviously too big to be a normal tree, being the only thing of the city to survive time, industrialization, wars. And in another post-apocalyptic world, a little cave has formed inside the tree, Erens grave, and someone, just like Ymir did in another time can now take the power of the titans again.
I am 99% sure that it can´t be Mikasa´s family, or not as close to be the grandson, because it must have passed hundreds of years. I mean, the city needs time to become like one of nowadays, and I´m guessing the war didnt happend right after the modern era. And it was a huuuuge war, it probably took time too. And then the nature keeps expanding. Around the tree has formed a big ass forest.
And if the boy is indeed from Mikasas bloodline, is still an Ackerman right? Is the thing about the Ackerman blood still working after finishing the thing with the titans? If it is, that boy wouldn´t be able to took the power, but if he take it, is not related to Mikasa...
But oh well, this is just what I have understood after reading it. It looks like an end for us to imagine another titan story, or the beginning of a new series.
Why upload the worst google translation i have ever seen over something that, although ugly was perfectly understandable