Another idea, did Klaus have to leave Skifander with Gil, not because anybody there would have killed him; but because Skifander itself was inhospitable to him? Perhaps Zeetha's green hair indicated that she got the proper genes from her mother to thrive; and Gil's brown hair indicated otherwise. Klaus could have been an exception because he's a construct, or because he was willing to shorten his own life, but not his son's.

He brought a changling child back from Faerie.

Still Klaus thought Zeetha was sent to kill Gil. A misunderstanding on his part?