"Are you a complete imbecile, Draco? The mudblood girl produced a patronus, and you could not. Do you realise how embarrassing this is?"

"Lucius, leave the boy alone. Shall I tell him how long it took you to cast a proper patronus? Oh yes, it's true. Your father was little more than a squib in those days…"

"Narcissa, I hardly think insulting me in front of the boy is going to help..."

"I was merely telling him the truth, darling."

"That depends on how you define the truth, dearest."

Draco smiled at his father's discomfort. "Expecto Patronum!"

Success!

"Thanks, Mum!"