Now basically everything in films and video games usually have stuff in it, as well as planned ideas that sometimes make it and sometimes are left out of the drawing board. Now what were stuff that was planned to be in the BTTF films but were taken out during production? I dont know if this was true or not but I remember hearing somewhere that in Part II when Marty is in the messed up 80's when Biff is head of the town, Marty runs into his sister who is a prostitute. But the reason why it was cut was because the actress who played Marty's sister was pregnant during the filming of the film. Is this mentioned in the DVD commentary? This is pretty much news to me.