The letter from the future details the regret felt by everyone for being unable to celebrate Kakeru's birthday. As such, high school Naho and the gang pester Kakeru about what he wants until the big day. On the other hand, 26 year-old Naho and the gang gather at the late Kakeru's grandmother's house to celebrate his birthday, like they had promised in the past.
It said the same thing in my letter.
.الشيء نفسه مكتوبٌ برسالتي
Das stand auch in meinem Brief.
Mi carta decía lo mismo.
Mi carta decía lo mismo.
Il est écrit la même chose 
dans ma lettre.
Sulla mia lettera
 c'è scritta la stessa cosa.
Isso também estava 
escrito na minha carta.
В моём письме тоже об этом написано.