Visit sites like Archive of Our Own (AO3) or Fanfiction.net . Search for the keywords "Gilraen" and "Cartas" (or "Letters"). If the story exists but not as a PDF, these sites usually have a "Download" button (top right on AO3) that lets you convert the story into a PDF instantly.
The second was to her son, Estel, written during his long absences in the wild. She had poured her soul into the pages, telling him of the quiet pride she felt as he grew into the likeness of the kings of old. She wrote of the small things—the way the sun caught the ivy on the terrace, the scent of the pines after a summer rain. She wanted him to know that even if he never took the throne, he was the king of her heart. But the rangers who were to deliver them were shadows in the night, and in the chaos of the encroaching darkness, the letters were tucked away for safekeeping and forgotten in the hollow of an ancient oak. cartas que no llegaron gilraen pdf