I can't seem to access that article without a subscription, but I have been reading online statements from Moon Unit how she and Dweezil are more or less frozen out by their other 2 siblings due to how their mother Gail handled her will or something along those lines. Moon seemed to indicate her mother was sort of controlling and perhaps not wrapped too tight. It's pretty sad. 

@jack_frost The article seems to be accessible on an every now and then basis.  Usually locked, but I got to read it on at least one occasion.

Mostly stuff you've heard before:  Frank, while super-duper talented - not a very good husband/father.  He and Gail (spouse) - probably not the best parents - kids not required to to attend regularly - none graduated high school.  Not only did Frank indulge himself with groupies on the road - he had them basically move into his home ... with his wife present.  After Frank's passing, Gail reconstructed his will.  Dweezil and Moon (the most "marketable"?) nearly cut out while the other two (Diva and Amhet) received the most.  Frank lived in a slight fear that Gail might someday find the family gun and seek some form of marital revenge.

Basic reconciliations (usually short lasting) - petty stuff like suing Dweezil out of performing as "Zappa Play Zappa" - making him bill himself as ZPZ (or something similar).

FZ was amazingly talented - one of my favorites of all time.  As a family though, the Zappas made the Connors ("Roseanne") look like the Nelsons (Ozzie and Harriet).  

As with Warren Zevon - wish I'd settled for the music without hearing about his personal life.

Mark Maron’s WTF podcast episode 1564 has an interview with Moon.