Fan Casting That THING Is Not My Child! in Sort by Tropes

A trope common to Speculative Fiction, in which a victim finds their genes, DNA, soul, or "essence" taken or copied without their permission, resulting in an offspring which is either unnatural or unwanted — or both. This being could be a clone, Half-Human Hybrid, Humanoid Abomination, or a Designer Baby created by a Stalker with a Test Tube. Sometimes, the villainous party may take what they want from the character's real offspring instead, twisting it with Body Horror, Demonic Possession or The Corruption, prompting the parent to now consider it a different entity entirely and deny any kinship. In any case, the clear message is that the parent DOES NOT WANT.