It is incredibly accurate. Stalin invented the personality cult. The fact of indoctrinating children early is a hallmark of Stalin's personality cult, it even made a transition to the personality cults of Mao, Kim Il-sung and his son and to a lesser extent Saddam Hussein.

The facts regarding Stalin's personality cult and what it meant for children growing up is pretty well documented. Children were encouraged to believe that everything good could and would come from Stalin. He was what would lead the nation and all of its inhabitants to greener pastures.

The state had artists of all stripes working to make Stalin into a mythical figure. Everything from children's books to posters to radio aimed in turn at young, adult and old were a real important part of the state apparatus. One instance of propaganda being aimed at kids, is the phrase "Thank you Comrade Stalin for a Happy Childhood!" became the center of a massive propaganda campaign.Which frankly, is what I think the book is referring to. It appeared EVERYWHERE.

One of the saddest things about the period is that even with all these efforts to indoctrinate the young, children did not escape the Great Purges... All this state propaganda was aimed at making children love Stalin but Stalin in return... Changed the criminal code so that people as young as 12 could be sentenced to the gulag on adult sentences. Stalin and his cult's relation to children was rather complicated.

It should also be noted that the communist movement as a whole made great efforts to appeal to the young. It started early in the Soviet Union, at 9 years old, you were expected to join the Young Pioneers if your parents wanted you to have any kind of future... Then at around 14, onward to Komsomol, the party youth league, which was part of obtaining full membership into the Communist Party.

If this is something that interests you, look for this ridiculously overpriced book. Its great but its expensive, might be a better idea to check it out of a library or something... But if you want to get some crazy personality cult action in book form, read "Under the Loving Care of the Fatherly Leader: North Korea and the Kim Dynasty". Since North Korea also has a Stalinist personality cult, it may interest you.

Edit: please note that by saying that Stalin invented the personality cult, I meant it in its colloquial sense, much in the way that you would say Caesar "conquered" Gaul. I know it was a product of various ministers and officials wanting to please Stalin and was an inherently collaborative effort (in a way). Hope that clears up the confusion.