Continuity mistake: In several episodes of the early seasons, Carson is said to have once been part of a music hall song-and-dance team with Charlie Grigg, who comes to Downton to blackmail Carson. But in later seasons, Carson is said to have come to Downton at a young age, serving as a hall boy.
Continuity mistake: Every letter's handwriting looks the same - no matter who wrote it.
Answer: Word gets around. The staff are gossips amongst themselves, but those loyal to the family know who to keep secrets from and who they can trust to share in the knowledge.
Phixius ★