"Why would be stop being friends?" Sirius frowned, as easily upset as he had been delighted by the idea of Severus having an idea to really upset his parents. He looked up at him, shaking his head. "Come on, Sev. You've been worried over that ever since we got sorted into different houses, but look at us now."

That was not to say that there had never been friction between them. Especially with the friction between James and Severus. Sirius knew that, but still. "Why do you worry about it? You'll get wrinkles all over your handsome face."