There was a stunned pause. No one had expected that.
"Well? Aren't you going to welcome me?" River asked. "Doctor, Amy, Rory… Ava."
Ava smiled back. "Hello River. Nice to finally speak to you. And be seen by you. Actually it is wonderful to be seen. So tell me, did the Doctor send you?"
"He did. You did too. Oh," she paused and handed her a piece of paper. "Co-ordinates. So that I can get here. And also, don't let him get the monkey. That's your cue."
Ava nodded.
"Wait. Sorry, sorry." Rory said, flinging up his hands. "You know her?"
"Course I do. She's the Doctor's best friend."
"Oh, not you too." The Doctor complained.
"She said you'd say that. She wants me to point out that you wouldn't have sent me here if, in the future, you didn't absolutely trust her."
Ava laughed. "I'm a genius! And here I was, afraid I was going to prove myself, through a DNA test or something."
The Doctor leaned forward, staring into River's eyes.
"Are you sure? She could of-"
"This is the part where I tell you that she didn't fake my memories, or torture me, bribe me or persuade me."
The Doctor glared at her. "How would you know?"
"Because I do."
"Well I still don't trust her."
"Oh, sweetie, I know that. But I have to be here. You two told me I had to. So…Here I am."
The Doctor frowned. "Fine then." He strode around her, unlocked the Tardis, and walked in. Amy and Rory swapped looks, but followed suit.
Ava looked at River. "So…this doesn't wear off then? I'm here to stay?" She kept calm, making sure not to let the hope seep into her voice. River gave her a smile.
"Nothing's certain." She said. Ava sighed, knowing that that meant both everything and nothing to her. But at least she was here now, even if it was only for a little while.
"Well then," she said, giving River a mischievous grin, "Let's get this over with then."