UPDATE: The outcome is the same even after I used Clean User Folder Approach. By the way, I decided to do another experiment on cousin relationship due to the outcome of cousin relationship after i deleted one of the sisters after taking the sisters to live mode and go back to the cas to delete her. So, this time, I only went back to the cas and deleted one of the sisters after taking both sisters to live mode. After that I returned to the live mode, I went back to cas again to delete the other sister, and miraculously the cousin relationship remained and were recognised as such by the CAS, relationship panel and family tree. Hence, I hope this glitch will be fixed soon since the nephew in my main save is already an elder (aunt is also an elder) and it's not like I can just create him a mother, and then re-create the sister relationship with his aunt (between nephew's mother and nephew's aunt).
The Sims Team
