Answer: I am afraid this is another old wives’ tail, although queens do display instinctive cannibalism towards dead and partially decomposed fetuses or a severely congenitally deformed kitten. At times, such a kitten may simply be rejected, i.e. not fed or groomed. Of course a runt kitten, the most poorly developed of the litter, starts under a handicap and may have difficult in competing with large and stronger kitten so that, due to malnutrition, it may not survive.
Sometimes a queen may overdo the licking and biting of the umbilical cord with the result that she damages the kitten’s abdominal wall and so-called ‘inadvertent cannibalism’ may occur, although this is rare. (This licking behaviour of the mother seems to be a response not to the kittens themselves but to the fluids produced at birth.) The very rare rejection of normal newborn kittens, or even aggressive attacks upon them, by the mother believed to be due to combination of changing hormone levels and stress.