Lydia Fairchild was confused. She had applied for state benefits to look after her three children, but according to DNA tests, she was not their mother. It was ridiculous – she knew full well that the children were hers, but she was being taken to court nonetheless.
The reason for this turned out to be that Lydia is a chimera, a person with the genetic material of 2 fused eggs. The genes in her hair and the genes from her cervix aren't the same, one being a match for her kids and the other not. For the full explanation and how it relates to sponges, see the link above. Can you imagine the murder mystery?