Season 4, Episode 7

Also known as: Alcohol poisoning

Doug's father was driving with a blood alcohol level of 0.33 (four times the legal limit) when he ran a stop sign at 120 mph, causing a fatal multi-vehicle accident that killed himself, his passenger Sherry Fox, and Pedro Lopez.

Also known as: COPD

Mark's father has emphysema from years of smoking and is on oxygen and albuterol inhaler therapy. He experiences coughing episodes and respiratory difficulty but continues to smoke despite medical advice.

Also known as: High blood pressure

Mark's mother was diagnosed with high blood pressure the previous year and is on medication, though she monitors it using machines at the base commissary rather than regular medical follow-up.