From PathfinderWiki

Prince That Howls
Source: Night of Frozen Shadows, pg(s). 71

A spirit-wolf in primordial times, Thron was one of the most powerful of his kind. He was known as the Prince That Howls, and he traveled the wilds of Golarion howling praises to life, love, and song. He had many mates and sired many more spirit-creatures, but two of his offspring transcended the power of spirits and became deities—the goddess Shelyn and the god Dou-Bral.1

When his son left Golarion and returned as Zon-Kuthon, Thron was overjoyed to see him again, twisted as he was, but the feeling was not mutual. Zon-Kuthon bound his father in razor-sharp chains, silenced his songs, and carried him off as a toy to be tortured. Over time, Thron's mind, body, and soul were stripped from him, and he now serves his sadistic master as his son's herald—the Prince in Chains.2 This shocking betrayal of their father turned Shelyn against Zon-Kuthon and incited another conflict between the siblings during which Shelyn was able to wrest Whisperer of Souls from Zon-Kuthon.1


For additional as-yet unincorporated sources about this subject, see the Meta page.