Family tree deleted

I have been playing with a save for 12 generations now and the family tree has sometimes been a bit buggy but nothign more than just not remembering all my sims. But now all of a sudden when i went to check the family tree everyone except for my current generation is gone. Like the sim im playing with right now and her parents show up and even that sims parents but it doesnt say that the great grandma is dead but when i try to summon her she cant be found. And all my progress is gone from every single generation before that. Almost my entire family tree is just gone, nothing is there, nada. I dont want it all to be gone. Does anyone know anyhting that could bring it back. Sadly i dont have a backup save that i can go back to  ☹️