Strengthening for knock knees?

So ladies I know that a lot of you are very clued-up on this type of thing. I have quite knock-knees - to the point where I can't have my knees and feet together at the same time. I'd like to try and help prevent any damage to my legs because of this and correct it a little if I can. Do you know of any exercises which might help strengthen the correct muscle groups? Love love xx