Children of undercover Russian spy couple only learned their nationality on flight to Moscow

That must have been quite a surprise! Raised, seemingly, in a regular family, they suddenly came to know about their parents' secret profession. Carrying on a normal childhood while their parents were involved in espionage must have been an intense experience for the children. Surprisingly, they only learnt about their actual nationality during their flight to Moscow. It would have been a huge revelation, possibly raising questions about their identity and the life they knew. Is there more to the story that you would like to know or discuss?