Good observation! It was the “level of panic” that made me initially assume the lady might be a nanny. But let’s not beat ourselves, or anybody else, up about drawing the wrong conclusion, because there are other reasons that reinforce this wrong conclusion too. For example as he was being asked his opinion on events in South Korea, I assumed he was based in the Far East, a region where it is common and affordable for professional families to have home help. I couldn’t hear the audio clearly enough to detect if the children said “mummy”, but even if they did I know that “mummy” if often the first thing my kids say in protestation if I’m preventing them from doing something they want. At the end of the day it doesn’t matter, the important thing is this video has brought joy and laughter to millions of people and ironically that’s probably the biggest impact on humanity the work of this professor is ever going to have. I just hope he and his wife had a good laugh about it afterwards too.