Taejun, you okay?

Remember the incident of Yeonwoo's parents death? When the police arrived to the scene, I briefly remember how it's Taejun who comforted him. Why isn't Taejun shocked, and seems calmer to the point that he's the one who calmed Yeonwoo down? At this rate, I'm starting to suspect that Taejun is the spark that inspires Yeonwoo to be like this but Taejun forgotten it, hence why Yeonwoo insisted for him to "return".