His phone rings, shattering the silence of the TARDIS. It’s always unexpected when his phone rings, but especially coming from the number that’s currently on the display. He taps the phone thoughtfully with his finger before answering.
“Hello?” he says cautiously, because he’s never heard an exploding brain over the phone before and he’s sure that he doesn’t want to hear it now.
“Doctor, it’s me, Donna. You do remember me, don’t you? I didn’t erase your memories or anything before you erased mine?” Her voice is just as he remembered it. There is no bitterness in her tone, just the light-hearted ribbing that followed them through their adventures together.
“What?” is all he can bring himself to say and she lets out a deep chuckle, a call-back to their first meeting.
“Time lord intelligence. Not so hard to figure out how to bypass the metacrisis once I remembered that it existed in the first place - we’ll be talking about that, don’t you worry. Just had to reroute some wires in the toaster and Mum’s not too pleased about what I had to do to the car, but Gramps is ecstatic. He wants you to come over for tea.”
“I’d love it,” he says and is already firing up the TARDIS before he’s hung up the phone.