Should smoking in houses with children be banned?

Now I know this would be hard to enforce but do you believe smoking inside houses with children should be banned or made illegal? We know that second hand smoke has over 7000 chemicals in it and at least 70 of those chemicals are cancer causing. Since 1964 approximately 2,500,000 non smokers have died from health problems caused by second hand smoke. In children second hand smoke can cause ear infections, more frequent and severe asthma attacks, coughing, sneezing, shortness of breath, respiratory infections and SIDS. In adults who have never smoked second hand smoke can cause heart disease, lung cancer and stroke. Children are helpless in the sense that if their parents or caregivers smoke in the house they have no say in being exposed to these chemicals that could cause health problems later in their life. In parts of Canada they have banned smoking in vehicles with children under 16 years old and if caught you can be fined. Should smoking in houses with children be banned? If so under what age? What would the penalty or fine be? How could it be enforced?