Iestin Edern is the older brother of a deceased mourner named Nissyen Edern. He is mentioned in Edern's journal. Not very much is said about Iestin, but it is said that he spends a lot of time in libraries in Prifddinas researching things about elven history. Some of Iestin's research has led him to the conclusion that Lord Iorwerth has somehow broken one of the 9 seals that Seren put in place to protect the Grand Library from the hands of men. It is not known why Lord Iorwerth would want to, but it is said that King Lathas of East Ardougne ordered him to do it and supplied him the means necessary. The name signed at the end of the Prifddinas report in Within the Light is also named Iestin.