"Million Dollar Listing" star Josh Flagg kept alive the tradition -- of rich kids getting richer -- by unloading his posh Hollywood home to another famous kid.
Flagg tells TMZ ... his now former house, just off the Sunset Strip, has had quite a run of celebrity owners -- and he just sold the quaint 2-bed, 2-bath 1700 sq. ft. home for $2 million.
Checkout the pedigree on the crib: Flagg, grandson of fashion mogul Edith Flagg ... bought it from David Katzenberg -- son of DreamWorks honcho Jeffrey Katzenberg -- for $1.6 mil back in 2013.
And now Josh is handing the keys to Nicolas Pakzad -- son of legendary designer Bijan Pakzad.
Rich kids ... struggling the same way none of us do.