Whatever they are doing that to reminds them of their mother. They think that they will get milk when they do that. It's not just kittens, cats of all ages do it.
They are cool to knead and suck.
Oh they'll suck her super dry.
It is believed that this is a throwback to when they were kittens. In kittens, kneading enhances the flow of milk from the mother cat, and it seems that this behavior is simply retained long after the need for it goes away.
It is a 'nursing' reaction. They could be hungry, or they are doing it as a way to comfort themselves.
knead
No. You must separate them immediately if you see them doing that. The kittens genitals will become inflamed and will require surgery that most of them do not survive.
Kittens like all mammals suck milk from their mother. Adult cats do not suck, but often lick up their food using the abrasive surface of their tongue. This may look similar to sucking, but it isn't.
This is a sign of utter contentment and to show trust and love to the owner. When they are tiny kittens and still feeding off their mum they knead the nipple they are suckling from to stimulate the milk supply and judging by the purring and funny little noises they make while they're doing it it's definitely got to be a state of bliss.
To knead is: amasar.
I believe it is 'knead'
The homphone for need is knead, as in to knead bread dough.
knead