Why Aren't My Kids Fat?

I'm really concerned. I don't restrict the consumption of candy, sodas, chips, cookies, cakes, crackers and any other forms of empty carbs, starch or sugar in my household. My childen chug sodas daily and they still have teeth. Amazingly, I do too. Since Cokes are as effective if not slightly more effective for chronic pain relief than massive doses of NSAIDs, I indulge in the more pleasant consumption of the delicious sodas. My ten year old plays video games all weekend while crunching fatty salty or sugar loaded snacks interspersed with pizzas and regular doses of chicken nuggets. She is SKINNY!! I have slathered her waffles with butter and drenched them in high fructose corn syrup to no avail. She is a waif, a non diabetic waif! What am I doing wrong? She rarely gets sick too. My teenager is like a graceful willow, and the stack of soda cans on her dresser belies her stature. How can this be possible? By all popular accounts of what is best for promoting weight gain, my children should be whoppers! How have I failed? I bring them candy bars regularly and I forbid over exertion, yet, they continue to fit into age appropriate sized clothes, or less in my youngest daughter's case. Shopping for her is a real nightmare! Maybe the secret is in the tap water? Maybe I need to feed them more hormonally grown foods? I allow free range food grazing and unlimited gaming binges, yet they continue on the path of not getting any fatter. This goes against all current media popscience! Hmmm. I wonder. Do they really have it all figured out, and who is it exactly that has funded these opinions? Now, before you faint in horror and think me profoundly abusive, I do admit that my children are indeed tortured with an array of multicolored vegetables, dairy products, whole grains and fruits regularly as well. Like I said: Free range food grazing here! And, just in case of cup cake overload, I nearly always provide back up vitamins in chewable or gummy form. The crux of all of this is..There must be a deeper underlying factor or factors in weight gain than mere diet and exercise....and..no one..knows what it is/they are!