This 78-year-old Connecticut jeweler balances wholesale and retail with ease and graceMike Rumanoff Rumanoff’s Fine Jewelry & Design Hamden, Conn. 62, third generation Steve Rumanoff  Rumanoff’s Fine Jewelry & Design Hamden, Conn. 59, third generation Doug Rumanoff  Rumanoff’s Fine Jewelry & Design Hamden, Conn. 36, fourth generation Leslie Rumanoff DeStefano Rumanoff’s Fine Jewelry & Design Hamden, Conn. 29, fourth generation   “I know a lot of people have their kids in their business because there’s nothing else they can do,” says retailer Mike Rumanoff, co-owner of Rumanoff’s Fine Jewelry & Design in Hamden, Conn. “My kids—they could have done anything.” The retailer’s progeny, 36-year-old Doug and 29-year-old Leslie, humbly shrug off their dad’s praise. But there’s no