Generations and Fam Tree Question

I'm sorry to hear that. The only time I played to a tenth generation was when I was doing the Pinstar Legacy Challenge. Then, I created forms for myself so that I could keep track of certain achievements that would reap points at the end. But more importantly, I had the generations listed. I know of no way to go back, unless you've kept earlier saves of your game. Unless you can pull from your memory the names of the lineage (direct line) of your Sims. Perhaps, someone else will come along with an answer for you.