In March 2010, Broderick was featured in the NBC program Who Do You Think You Are?. Broderick stated that his participation in the ancestry research program emotionally reconnected him with the role he played in Glory 22 years earlier, as he discovered a paternal great-great-grandfather, Robert Martindale, who actually was a Union soldier. A veteran of the Battle of Gettysburg, Martindale, who belonged to the 20th Connecticut, was killed in the aftermath of the Battle of Atlanta and was eventually interred in an unnamed grave at the Marietta National Cemetery. Having identified the grave with the help of historian Brad Quinlin, Broderick's research enabled him to give his ancestor his name back. In the same program, Broderick discovered that his paternal grandfather, James Joseph Broderick II, whom he had never known, had been a highly decorated combat medic in World War I, having earned his distinctions during the Meuse-Argonne Offensive.