'I'm not trying to be a hero, but seriously, Sirius Black can't be worse than Voldemort, can he?'
Mr Weasley flinched at the sound of the name, but overlooked it.
'Harry, I knew you were, well, made of stronger stuff than Fudge seems to think, and I'm obviously pleased that you're not scared, but —'
'Arthur!' called Mrs Weasley, who was now shepherding the rest onto the train.
'Arthur, what are you doing? It's about to go!'
'He's coming, Molly!' said Mr Weasley, but he turned back to Harry and kept talking in a lower and more hurried voice.
'Listen, I want you to give me your word —'
'— that I'll be a good boy and stay in the castle?' said Harry gloomily.
'Not entirely,' said Mr Weasley, who looked more serious than Harry had ever seen him.
'Harry, swear to me you won't go looking for Black.' Harry stared. 'What?'
There was a loud whistle.
Guards were walking along the train, slamming all the doors shut.
'Promise me, Harry,' said Mr Weasley, talking more quickly still, 'that whatever happens —'
'Why would I go looking for someone I know wants to kill me?' said Harry blankly.
'Swear to me that whatever you might hear —'
'Arthur, quickly!' cried Mrs Weasley.
Steam was billowing from the train; it had started to move.
Harry ran to the compartment door and Ron threw it open and stood back to let him on.
They leant out of the window and waved at Mr and Mrs Weasley until the train turned a corner and blocked them from view.