Duke never taught his kids how to change the air filters in the Heating & Air Conditioning device in their home. The twins were residing on their own for the first time while attending university. Duke gave them 2 cartons of air filters that matched the Heating & Air Conditioning device. He even changed the outdated air filter for the twins. Duke didn’t believe that something as direct as an air filter change would be something that had to be demonstrated. A while later Duke went to check on the twins, and was surprised at the poor air quality in their home. He inquired why they were not changing the air filters. His twins shrugged and admitted they didn’t know how to do it. Duke said they might at least look up how to do that if they were unsure or call him up and he would have demonstrated via video chat. The twins responded they were busy with studies and extracurricular activities that they just didn’t have the time to do so. They added that when they got home, it was usually too late to call their dad anyway for something like changing an air filter for the Heating & Air Conditioning system. After hearing what they were saying, Duke chose to demonstrate that then. He showed his twins exactly how to get to the outdated air filter to pull it out. The old filter was in a slot directly next to the Heating & Air Conditioning device that fit into the air duct. It was self-explanatory to pull out and put the modern air filter in. Duke had to stress that the twins needed to make sure the arrow was pointing in the right direction because you didn’t want to install the air filter backwards. He was surprised at how self-explanatory it was to do, and they never had to endure poor air quality again.