Dear PF Forum, Sorry if I ask (again) about twin paradox, after so many question about this topic here. Supposed T is a star 100 ly from earth. If B travels to T from earth A. Is the symmetry broken? B. If B watches A's clock at Earth and A watches B's clock at T, do they see the other clock late by 100 years, no matter how fast B travels? Now B travels back to A, and now B brings a companion C, to travel with him, sitting beside B C. Is the symmetry broken for A and B? D. If the symmetry is broken for A and B, what about for B and C? 1. Does B sees C age faster along the journey? 2. Does B sees C gesture/act in fast motion? 3. Does C sees B gesture/act in slow motion? Thanks for the answer, and pardon me for this twins paradox again.