Episode #4.4 - S4-E4
Character mistake: When everyone is preparing to go in to dinner, Robert is wearing an adjustable bow tie. It's bad enough he's wearing black tie to dinner when he has guests, as his mother points out, but Robert, the Earl of Grantham, absolutely would not be seen wearing an adjustable tie with a stand up shirt collar, even among only his immediate family. (00:35:15)
Character mistake: At one point they say the gramophone was gift for Sybil's wedding. Later they say don't play the gramophone from Mary's wedding, it will make Edith sad.
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 ★