"You'd rather hang out with filthy wizards than your own brother?" Regulus sneered at Sirius.
Sirius looked upset. "If you haven't forgotten, I'm a Gryffindor. Those are my friends in that compartment. I'm going whether you want to join me or not."
Regulus grit his teeth but followed Sirius into the compartment with all of his filthy friends.
"Where's James?" Sirius asked.
Regulus had heard all about this 'James' from his brother. Who was this bloke who Sirius thought was another brother?
"Ah, sorry, I'm a bit late."
Regulus felt his eyes widen in surprise. So this was James Potter.