Another notable counter-example: the Kinks, even with occasional discord between Ray and Dave Davies, lasted over two decades as a modest-to-significant commercial success, and another decade -- from about 1985 through 1996 -- as a shadow of their former selves, both critically and commercially.
That article is flat-out shitty journalism. You have to push pretty hard to shoehorn Duane Allman dying into a story about sibling discord. And saying that Ann and Nancy Wilson "made up" is false too, in that it suggests that their hiatus had to do with conflict instead of just not making music for a little while. Mostly the story is just an excuse to say "here are some bands that had siblings in them, and most of them eventually broke up." That's true of most bands.
What makes it flat-out shittier is that it ignores even more obvious examples of its thesis (the Beach Boys, Credence), in addition to overlooking many examples that contradict the thesis (the Neville Brothers, for example).But, bottom line, Isaac is right: It generally doesn't work out long-term for any rock group, regardless of family ties.
Just looked at a website entry for Barry Gibb that estimates his fortune at $40 million. Could it possibly be that he made that little money or squandered that much...
I do not wish the Jonas Brothers well in future endeavors. I don't wish them ill, but I don't wish them well.