The daughter of someone I know has just had a baby! Sadly she insisted that the cat had to go. Her argument was that she had heard that cats become jealous of a new arrival - lie on a cot and smother the baby and even suck the breath out of them because they are attracted to the baby by the smell of breast milk! This myth does go back some way and is recorded in a Plymouth Coroner's inquest of 1791 that the cat had sucked the breath out of a child and caused its death.
This is probably an instance of Sudden Infant Death Syndrome - but the fact that even in the 21st Century ancient tales against the cat are still part of spoken folk law is interesting even if it is total rubbish!