[NEEDS SAVES] Save Game Progress partly reset (Patch 1.109.185)

Product: The Sims 4
Platform:PC
Which language are you playing the game in? Deutsch
How often does the bug occur? Every time (100%)
What is your current game version number? 1.109.185.1030 DX11
What expansions, game packs, and stuff packs do you have installed? Expansionpacks: all buf For Rent Gameplay Packs: all but Werewolfes, MWS, Batuu, Strangerville, Vampires Stuff packs: all but bowling and spooky stuff Kits: modern lux, Pastell pop, desert, little campers, maximalist, blooming rooms, Incheon, fashion street, Paola Locatelli Set
Steps: How can we find the bug ourselves? Open you last save game?
What happens when the bug occurs? Corrupted Savefile
What do you expect to see? My Sim where I left him
Have you installed any customization with the game, e.g. Custom Content or Mods? Not now. I've removed them.
Did this issue appear after a specific patch or change you made to your system? Yes
Please describe the patch or change you made. Downloaded the September 18th update

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My Save file is completely corrupted. On the loading screen I still see the family as it should be. 

I moved out my heir. Played through like 1-2 Sim weeks with him. He was married with kids. All moved in into a new house I build a minute before closing my game. 

When I go in now the house is still there, but he is a teen again living with his family. All of my progress gone. 

I tried an older save file and all are the same. It's the date of his birthday and he is back in his family. The new house is saved in different stages. 

I started with mods (outdated) and without mods. 

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