Clara doesn't ask, he doesn't explain, simply tucking the phone away again once everything's saved. It'll be a good project to work on when he's bored at the office and throwing pencils at people.

The suggestion however earns the usual cracked smile. He is not a good measurement on whether something is 'mean' or not, so that part goes unacknowledged. "You're a ghost story, remember? Maybe appear to one of them and just keep saying they're your son and you both need to go home. They'll immediately assume you're trying to spirit them away," the emphasis is punctuated with one hand waved through the air, the universal gesture of 'stupid magic nonsense', "Or some other ridiculous trope."

See, that is too mean.

"The angry frowning face is perfect. Keep it."