Ho-ho-hoooo... Hello, dear listener, welcome to this Xmas episode! I'll tell you two stories this time. One is about how the popular belief according to which Santa doesn't visit naughty children may be or may be not (listen and find out) actually true. The other story, given the year is 2020, is about what would be the consequences of Santa Claus doing his worldwide tour on Christmas Eve while infected by a highly contagious virus. Here's the script (with the bibliography): https://tinyurl.com/y784b9e3. Enjoy&Merry Xmas&peaceful holidays! @sciencemug