Link Memories are groups of thoughts Dreamweavers acquire via Mind Links with other Dreamweavers. These memories are gained from any Dreamweaver who has passed memories on, and it isn't uncommon to have old memories, including those of Mirar's, because they were passed through generations of Dreamweavers.
|Spoilers from "Priestess of the White"|
Leiard discovered that he had many of Mirar's Link Memories but he thought that it was because he had linked many times. When he met Arleej in Somrey, she told him that it was unusual to have that amount of his memories.