Watch : How Jamie Chung and Bryan Greenberg Navigated Their Twins' Time in the NICUJamie Chung knows firsthand how difficult the first days of motherhood can be. And the Big Hero 6 actress and husband Bryan Greenberg had an especially tough time as their now 4-year-old twin boys spent their first weeks in the neonatal intensive care unit (NICU) after they were born prematurely. “One had a two-week stint and then graduated,” Jamie shared in an exclusive interview with E! “Our other child was there for a week.”And as the 42-year-old explained, it was a “really scary experience” for both her and Bryan, 47, as they were first time parents holding their boys who were barely four pounds. “You're hearing the heart rate monitors and seeing all these incubators,” Jamie recalled, “and what a wonderful thing to have these wonderful NICU nurses hold your hand through this entire experience, because it can be quite traumatizing.”For the former reality star and her husband of 10 years, it really was just them and the NICU nurses navigating the experience together because their family wasn’t able to visit.