Actor Choi Ji-woo makes her return to the big screen after three years with an independent film based on the true story of a family navigating life after their son is diagnosed with diabetes. "I was cautious because I had to portray a real-life figure," Choi said during a press conference Thursday for the upcoming film "Sugar." A mother of a young daughter herself, the actress said she could immerse herself in the role more easily than she would have before experiencing motherhood. "I tried not to appear too emotional on screen and actually had to hold back my feelings throughout the performance," the "Winter Sonata" star said. She explained her character, Mi-ra, as a mother who bravely accepts a new reality: Her 12-year-old son, active in his school's baseball club, is suddenly diagnosed with Type 1 diabetes — a chronic autoimmune disorder that stops the body from producing insulin to regulate blood sugar. Mi-ra, an engineer, secures a device from overseas that can measure blood sugar without drawing blood, sparing young patients from painful finger pricks required multiple times throu