Cassidy's great-grandmother on her father's side was
Helia, the Salamander from Corruption of Champions. She has little good to say about her, and even less to say about her paternal great-grandfather; Cassidy's grandmother ended up in Eden when she realised her own father was so corrupt that he was grooming her to become his sexual plaything, and Helia was such a (probably corrupted) slut that she either didn't realise or didn't care. This shocked "
Helspawn" straight and scared her away from her family home, and as a result she has striven to keep her children from falling to similar depths.
Cassidy's creator has stated publicly that this backstory and the character in general, which were written with Savin's approval, were created as a finger in the eye of the infamous vocal minority whose incessant demands for incest content for Helspawn caused the character to be dropped.