I noticed something while going through The Repairer of Reputations for part two of The King in Yellow mini-series. I had named the main character incorrectly. The main character of that short story was named Hildred Castaigne. Hildred was, however, the son of Hastur.
It may be interesting to note though, that a certain author (and a few others), while reworking the entire Lovecraft universe, called the King in Yellow an avatar of Hastur, who in turn was one of the Great Old Ones. It will also be of interest that Lovecraft was in turn inspired by the work of R. W. Chambers, and included symbolism from the King in Yellow in some of his stories.