High Cholestorol

My daughter has been sick for coming up to 4 weeks now, it started with a sinus infection which spread to throat infection. 5 bottles of antibiotics latter she was clear of all infections but still sick, so based on mothers instincts I asked the doctor to do a blood test just to get a general screen to see if there was anything underlining.
Anyway, I received the results today and have been told she has high cholesterol (as well as very high B12, low vit D and a virus of unknown origin).

How on earth does a child who is only 30kg and 141cm tall, the majority of her food is potato, pasta, weetbix, rice and soy milk (with occasional beans and mince) get high cholesterol????

I have been told to reduce the fat in her diet but where is the fat to begin with?? if I take anything out she will lose weight again. I dont use oil in her diet and I have looked at all of the processed foods she eats and they are labelled no cholesterol.

I am seeing the doctor again in a couple of weeks and can have more of a discussion on it when we see him but this really has me stumped.