We have four children, the youngest is 15, oldest 26. It is very hard to low carb when we need to feed them too. Much as I look at things they eat with boggle eyes and eyebrows in my hairline, I won't stop them eating the yummy carb laden stuff. We have cut down the carb-laden stuff we bring into the house however. They are all aware of the dangers of carbs, and that there is such a thing as hereditary diabetes, so they are beginning to control their carb intake by themselves. The oldest boy had a coke habit - at least 4 cans of cola per day - he's stopped that completely. He also works out daily on his Wii. The younger two boys are much more conscious that putting junk into your body causes damage you cannot see, and our only daughter put on such a lot of weight whilst writing her dissertation and revising that she also low carbs.
I found that the way to be the carb cravings was to take either Banaba Leaf or Gymnema Sylvestre supplements, although supplements aren't everyone's choice.
Ju