That's Walden and April Derleth above, the children of August Derleth. April died yesterday. Here is the notice from Locus Online News:
"Publisher APRIL R[OSE] DERLETH, 56, died March 21, 2011. The daughter of author August Derleth, April was co-owner of Arkham House with her brother Walden Derleth, and ran the company as president and CEO starting in 2002.
"April Derleth was born August 9, 1954. Her parents divorced when she was five years old, and her father retained custody. August Derleth co-founded Arkham House in 1939 with Donald Wandrei. After August Derleth's death in 1971, Wandrei briefly served as editorial director until being succeeded by James Turner, who oversaw operations until April Derleth took over. She sought to shift the house's focus back to its original emphasis on classic weird fiction. Arkham House has announced that sales and unfulfilled orders will be temporarily suspended."
This is very sad indeed, because Miss Derleth brought Arkham House back to life after years of dormancy, with two excellent new editors and many new books planned and announced. I myself am working on a story for Arkham Nightmares, a new Arkham House anthology edited by the wonderful Lois Gresh, whom I had the pleasure of meeting at Mythos Con. August Derleth has been on my mind of late, and I have just started recording a series of vlogs concerning his "posthumous collaborations" with H. P. Lovecraft. It is my fervent prayer that Arkham House can survive and continue under new direction. Peace unto April Rose Derleth.