This continues to be a problem with no mods, no CC, no nothing added to the game. I suspect it has more to do with completing a collection (possibly frogs) than any mod.
At this point I have also accepted that EA is not going to fix this issue. It really has made the game unplayable for me, and I have not played the game in months. I cannot collect, I cannot design (no CASt), Sims disappear while I am talking to them. I went back to TS3. I have not bought the camping pack for TS4 and will not buy GTW. It is extremely unlikely that I will buy anything for TS4 at this point.
