It is a common issue and I wish I had any permanently working solution. For me it was always enough to restart the game when it happend but it seems to be becoming more and more common.
Where the Sims supernaturals and do you also have pets in your household ? Does the same happen if you make normal Sims ?
Just to note, still happening to me :S and my sims are all vampires, in my household, and i don't own the pets game add on, i have supernatural and ambitions, *so far* planning on getting pets soon, when i can, and when you say normal sims, do you mean human sims? just standard, if so i aint tryed that yet, while i wait on reply ill give it a shot and see what happens.
I don't know if this issue is recent or not, when i used to play after supernatural came out i started as witches, and never had the issue, only just came back to the game and made a vampire family, so ill also check other classes out aswell see what happens, hopefully speak again soon.
Shall post the update on what happens after i try them out for a couple of hours, see what happens, just i like the vampire snow, would be a pain if it's only the vampires that are effected with this issue.
The issue seems to get worse with every patch and I wished I had a solution that works every time.
What happnes is this: When you switch Sims, the game is supposed to unload the old Sim and load the info of the new one. Now with the error, something makes the process fail and the old info isn't unloaded properly.
That something can be any number of things which makes this so hard to solve.
And yes, by normal Sims, I mean human Sims.
Aye i tryed as human, still same occuring issue :S, still no cheats used but still happens :S unistalled in 3 times now and reinstalled it, same happens for all classes, human, fairy, vampire and werewfolf that iv tryed, and all of them are effected by this issue again :S it's really starting to get annoyying :S, but im actaully 8 days into a new save, new record for recent saves :P as a witch, hopefully this does not become effect likethe others, tho i do not understand why the witch seems to be fine, yet all other classes are all effected, this save may become effected soon, hopefully it doesnt, i've tryed so many different things now and i never get any results :S it seems everyone who has this issue still all have the issue :L i just hope a soluation arises soon and it's sorted, i would like the start my vampire save =D
Sorry, I couldn't be of more help. The issue is a pain, i've experienced it myself but luckily for me, it was never lasting.
I do use a lot of mods to remedy all those issues thought.
