[Lily's eyes still widen despite herself. She supposes she's not getting used to the notion any time soon, but she dips her head, with a smile.]

There was one time when you were diarrhea and had bolted the loo shut on account of needing the whole area to yourself, and the time when you were out of commission for drinking Pettigrew's rat tunic. On that note, when did he ever keep a rat?