Fortunately the domestic cat is adaptable enough that a 'happy families' situation usually prevails. Kitten killing is more common in inexperienced or highly stressed mothers and, because the surviving kittens of a kitten killer may grow up into poor mothers themselves, there may be some genetic problems (leading to hormonal or behavioral problems) influencing kitten killing behavior in queens. In males, the kitten-killing behavior is most often due to their highly competitive natures, something which has been modified by selective breeding but which has not been entirely eliminated as it is part and parcel of the male instinct.