The fact that Thomas would be exceptionally good at cricket is not a coincidence; footmen were chosen for their physical attributes. Factors such as athleticism, height and good looks played a large part in their employment.
Lady Mary uses the alias "Mrs. Levinson" when in London to see the doctor about her difficulty conceiving. Levinson is the maiden name of her mother, Cora, Countess of Grantham.
The episode won an Emmy Award for Outstanding Music Composition for a Series (Original Dramatic Score).
What came to be known as a "Ponzi Scheme" was described by Charles Dickens in his 1844 novel "Martin Chuzzlewit" and in a later work, "Little Dorritt." Charles Ponzi, who made the pyramid scheme infamous, was not born yet.
Edith tells her aunt that she likes Warwick Square. Laura Carmichael who plays Edith later played Margaret Pole whose grandfather was Richard Neville, Lord Warwick or Warwick the Kingmaker in The Spanish Princess.