Kneading, also called “making biscuits”, happens when the cat will push out and pull in their front paws, alternating between right and left limbs. The cat is also purring loudly and she is enjoying the moment.
Kneading is an instinctive trait for cats. Kittens “knead” the breast while eating, using the forelimbs one at a time in an alternating pattern to push against the mammary glands to stimulate lactation in the mother. Almost all adult cats will knead. They carry these behaviors beyond nursing into adulthood.
When cats knead, the scent glands on the pads of their feet will mark the surface being kneaded. So, the scent left is a territorial marker. When a cat is kneading you she is saying that she owns you but also that she feels safe with you!
Kneading is a natural things for cats to do. It’s nothing wrong with the cats when they are kneading.