Verbal irony is when what is said is the opposite of the literal meaning. One type of verbal irony is sarcasm, where the speaker says the opposite of what he or she means in order to show contempt or mock. Other types of verbal irony include overstatement (or exaggeration) and understatement.
Thanks for A2A. There are two excellent, well-informed answers here, so I'll just try to simplify. Dr. Falconer is of course correct; pre-weaning age (about 9 weeks or younger) kittens can drink cow's milk, or any milk. Neonates are not lactose intolerant; this develops gradually with age.
An ill mother cat may not be able to nurse her babies. During their first four weeks of life, kittens need their mother's milk. If both the mother cat and her kittens are happy, healthy and well-cared for, there should be no problems. Unfortunately, if the mom becomes ill and can't produce enough milk to feed her kittens, she may reject them.