[wheelinsupial]

They do not cite it, but searching that sentence on Google brings up a few articles mentioning a “20-year study by The Williams Group involving 3200 families, show that 70% of families lose their wealth in the second generation and 90% lose it in the third.”

But I can’t find an article in a quick check on er website.

There are some mentions on their website about how splitting the family fortune dilutes it and causes families to lose money.

There are families in Europe that pass the bulk of the family fortune to the oldest son. That son does what they can to help the rest of the family live comfortably, but the rest certainly aren’t rich. So, this statistic may only be applicable to American families or places where it’s common to successively divide the fortune up.