OP here, I am the child of a physician and worked in the medical field for half my working career. In my year of working for a pediatrician as a medical assistant and in the front office, I saw the pharmaceutical reps pushing medications with incentives to the doctor and office. I also worked in pharmacy for quite a while. This was at least 10 years ago, actually longer.
Anyway, it's a good point to say that these people have an underdeveloped immune system. It supports my theory and the theory of many that conventional medicine including vaccines causes an underdeveloped immune system and why many people get sick from vaccines. Getting vaccines from birth and antibiotics as well as many other medications to deal with symptoms every time someone is sick doesn't give the immune system a chance to figure out what it is suppose to do. Conventional medical "wisdom" interferes with peoples immune system with every possible opportunity, before birth, at birth and for ones whole life if people allow it. The sickest people I know, as with the above family, seek the care of a doctor regularly. There is certainly a time and place for conventional medicine. I would be dead without it as in the case of my ectopic pregnancy. Then again, if I hadn't had a c-section I would have never had the scar tissue that caused it to begin with.
I was sick for years due to conventional medical care and as soon as I started relying on more natural ways, I started to get better. I received lots of vaccines as a young adult to work in the hospital, I have suffered chronic fatigue and joint pain since then.
The majority of people who get vaccine associated diseases have been vaccinated since the majority of the population is vaccinated. Vaccines may work to some degree, but they also cause a lot of damage including not allowing the immune system to learn (it cannot do that with dead bacteria and viruses, metals, animal tissues, preservatives which are injected directly into the body bypassing the nose, skin, eyes and mouth which is how we normally catch these bugs to begin with). It is very logical if you think about it. Of course this family has and underdeveloped immune system!