OK, 2 things.
1. I usually use the original titles in my posts. So, since this documentary is German, it is "Stalins tochter". I got confused between Australian subtitles, and continuous jumping between Russian, English and German.
2. I mentioned this documentary to my parents. They said they lived through it and remembered the whole thing. Amazingly, my mother was good friends with Gregory Morozov, Stalin's daughter's 1st husband. And my father spent a week in a posh sanatorium called Sosni with Stalin's parents-in-law in the same place. They were old and he was 13 in 1944, so they never associated. But he remembers people wispering "Stalin's relatives" and the general atmosphere of uneasiness, because one never knew whom Stalin would kill.
I was surpised that a sanatorium like this was operating, even though with some food shortages and heating problems. I also asked them if regular schools were open in general in USSR during the war, and the answer was "yes". I have a picture of total destruction but obviously some areas removed from the front were operating normally.