I'm so sorry. Yes definitely no genetic link.

Is tick-borne disease still high on your list? I know you saw a LLMD. Has anyone in your family taken any type of lyme tests? Even the conventional elisa screen or western blot? If this were me, I'd put this higher on my list of potential causes.

You all drink and bathe in city water, correct? There are chemists whose full time job is to test and assess the quality of your city water (I have friends who do this). I'd probably put this lower on my list, especially if there aren't other families in your neighborhood having issues.

You said you've never seen any black mold. So perhaps this is lower on your list. There is a test called ERMI test, which tests the VOCs from mold that land in the dust of your home. Most mold testing companies just test the air quality, which is not what is necessarily making people unwell. I'm not very familiar with the topic of mold yet, it's something that I just started researching.

You already tested yourself for heavy metals? Which panel did you run? You were negative for lead, correct (lead paint)? I know I've mentioned radon before...how about asbestos? Do you a working carbon monoxide detectors on all levels of your home?

Any family vacations out of the country? Any rounds of vaccinations, especially like the rabies vaccine?

Where do you buy your food - grocery store, farmers market, grow your own? Maybe you could change some of this up. You are very knowledgeable about nutrition, so I'm sure you pulled gluten, dairy, and soy out of the family diet to see if if helps. Are there any supplements that you have the whole family taking?

Sorry for all my random thoughts, but I'm just trying to cast the net as wide as possible.