‘Making biscuits’ is definitely an instinctual habit, as newborn kittens will knead their mothers' belly while nursing. An older theory was that if an adult cat did this, it was a sign that it had been weaned from its mother too early. But seeing as this habit can be observed to some degree in all adult cats, we’ll have to leave that one out. Here are three other theories as to why cats ‘make biscuits’.