*Little Y/N is busy drawing*
Greg: Wow, that’s a brilliant butterfly, kiddo!
Little Y/N: It's not a butterfly. It's a moth. Chrysiridia rhipheus. The Madagascan sunset moth.
Greg: Oh! Right. Moth. Of course. How do you… tell the difference?
Little Y/N: Butterflies have club-shaped antennae. Moths have feathery antennae. It’s a primary morphological distinction. It is diurnal, which is unusual for the order Lepidoptera, but its wing venation and frenulum are definitively moth-like.
Greg just stares, completely out of his depth. Sherlock, who has been observing from his chair, allows himself a proud smile.
Sherlock: You see, Lestrade? Precision. That’s what’s always lacking in your case reports. You call a moth a butterfly. The details matter. They always matter.