@melodymich574 , I know this used to happen a while ago with Sims that were Alien/Vampire Hybrids, but they were supposed to have made it to where this combination wouldn't be possible anymore. (I used to test Alien/Vampire combinations a lot a few years ago, but since they changed it, I haven't tried it again to see how it differs from before).
I also haven't played with Alien/Human hybrids in a long while, but I never had this problem with them, only with the Vampire/Alien hybrids. 🤷♀️
Are you on a console or a PC or Mac? If you are on a PC or Mac, do you use any Mods or Custom Content (CC)?🤔 Outdated Mods/CC can cause problems in your game so if you have any outdated Mods/CC you will have to delete them, and check with their creators to see if they have made newer versions of them that are compatible with the latest game update, which happened on October 6th. You will also have to delete the local thumb cache.package file because this will tend to keep outdated and corrupted data even if you delete the outdated Mods/CC! 😞
To test to see if the problem is outdated Mods or CC please do all of the following in order:
1) Move the Mods Folder to your desktop
2) Delete The localthumbcache.package file in the game folder. (This is very important!) 🤨
3) Fix you game in Origin by logging in and go to Library, then right-click on The Sims 4 and choose the "Repair Game" option from the list. Wait until Origin finishes repairing all your packs and not just the base game. If you are on a Mac it will only repair the base game. Do not put your Mods folder back into you game yet!
4) Now, when you turn on your game again, it will create a new mods folder that will be empty. Check to see if your game is now working without mods/CC.
5) Now you can try adding back items from your Mods folder one at a time checking your game each time to see which item is causing your game to not work properly. If you have a lot of items, you can try the 50/50 Method, testing in batches.
The CC creators will usually update the CC items and Mods after these updates, so when you find out which one is the culprit, you can get the updated version from whoever made that item of CC in the first place. You should try these steps anytime you have problems in your game to rule out CC/Mods problems. It is the responsibility of the Mods/CC creators to update their items anytime EA releases a patch/update, and it is the responsibility of the people who use Mods/CC to make sure they are using the most recent version, which in this case was on October 6th. After you have deleted all outdated/broken Mods and CC and deleted the local thumb cache.package file, you can return your Mods folder to your game. 🙂
Please update us on your situation! 😇