So how to commit murder and not get caught. Well anything that causes inflammation will automatically shorten life, increase pain, heart disease and cancer. So buy the object of your disaffection lots of candy, cake and sweets of all kinds. Reduce the vitamin content of their diet by not cooking vegitables for them or cooking them so they are soggy and don't forget to throw out the water they were cooked in.
Encourage them to stay in the house and avoid the sun. Pretty simple and no one will figure it out. Lastly do not be discouraged that this may take a long time. We are seeing increased cancer and cardiovascular disease in younger and younger population of people. Some in their teens. Could it be diet and life style. Last of all let your children eat anything they want. After all disapline in the family and schools is not a good thing.
Obviously, I don't believe the above is what should be done. Just trying to make a point or two.