This mod is no longer needed
The mod fixes an LE that occurs if you try a save in which the game tries do update the family dynamics but runs into an error.
The game tries to set relationship bits between two Sims but at least one of the Sims doesn’t exist in the game anymore which leads to the error.
The mod prevents the code from running if one of the Sims doesn’t exist hence preventing the error. The actual reason why the game is trying to set that bit is unclear and needs to be fixed my Maxis.