A few people commented on some similarities between some of the characters and their relationships...Sherlock and John ought to take a leaf out of Anita and David's book, hmm?
Familiar
"Sherlock, why are you and Mycroft the way that you are?"
"How do you mean, John? Personality?"
"Yes. And dynamics." John slipped forward and sat on the edge of the bed. "If you don't mind me asking."
"You know you can ask me anything, John." Sherlock cleared his throat. "Mycroft and I take after our father in personality, being somewhat sharp, arrogant, and calculating except when around those we love. We're quite different from Mummy, who's very warm, gentle, and open-hearted."
Something about what Sherlock was saying struck John as familiar, but he couldn't figure out what.
Prompt was from Sailasiri Culnamo, and it was: sharp