BY CHRISTINA BINKLEY

Milan

At the headquarters of the Italian fashion house Etro here on the Via Spartaco, women's wear designer Veronica Etro can shout across the studio at her brother Kean, who designs the brand's menswear. Close by are her brothers Ippolito, Etro's general manager, and Jacopo, who oversees textiles and leather.

They often meet in the basement kitchen where Ippolito will rein in his siblings' spending plans over impromptu lunches. "Discussions in the sandbox," is how Jacopo describes these meetings, which can range from businesslike to raucously angry.

While they're relatively rare in the U.S., dynasties that remain in family control ...