Sometimes.

[She thinks of the twins sending up a fireworks display instead of giving her a chance to see them off. Percy leaving a note on the kitchen counter. And then there was Harry's hand in hers before he stepped through the door and she tried to follow.]

Sometimes there's a chance. A door'll open or... or you'll have enough time to leave a letter or a message on the network. Or you'll just go. It's an unfair promise to ask of anyone, I suppose, but I'm a bit selfish that way.