Hello Everyone!
I just would like to give some hope to all of you parents and children out there. My little sister suffered from really bad KP that started when she was about 9 years old til she was around 13 to 14. She had KP all over her face especially on her cheeks. It looked almost like really bad acne, but not red, and her bumps was really big and the skin was so rough. The only thing that would calm it down a little was The Body Shop´s body butter with mango or The Body Shop´s Cocoa Butter lotion. Regarding your child is not allergic to any of the ingrediences it´s worth a try.
The good news is that when she turned in to her early teens she totally outgrew it, no acne or nothing. Now she has the best skin in the whole family, really smooth and clear. So it seems that children really can outgrow this condition. I got KP as an adult and that seems harder to get rid of. So keep your hope up that your child will outgrow this too.