Why does my kitty do this......

.....and how do I get her to stop?

Lily, our kitty, who is between 3-4 months old, has this habit of burying her face in our sweaters and kneading her paws at the same time. She typically starts this in the evenings when we're sitting down to relax after dinner and if we don't stop her, our clothing ends up wet in the spot she was working on. Needless to say, it's driving us a little crazy, lol. I'd really like to discourage this behavior so it doesn't continue but if it's an instinct of sorts, I don't know that anything can be done. Or is there?
It kinda reminds me of when they're nursing on their mothers but I don't get why she's doing it to us.

Thanks in advance,
Erynne