Sollertree ("Soll"), formerly known as "Skyspike," was a solitairy hedgehog who was a good friend of the otter Goodwife Brimm. He was the husband of Beechtip and fathered a daughter called Nettlebud. His wife was killed and his daughter kidnapped in a vermin raid. After this, he settled down growing nuts that he was quite fond of along with his pet frog Croikle, who was named after the sound he made. He re-built his home again after looking for his daughter for many seasons. He aided Song, Dann, Burble, and Dippler; and later reunited with his long-lost daughter.