He gave her a little nod of agreement as she suggested that he had to catch up with his family. "Susan... fell in love with this human called David while she was traveling with me," he started to explain, not even sure why he was bothering but he supposed that if she knew a little more about the situation she might find it easier to accept. "I locked her out the TARDIS and told her to stay with him, and one day I'd return to find her. She stayed, she had a family, and eventually she had to watch him and her family die off around her," he said, looking at his feet instead of at Rose, not realising how the whole speech sounded to a human he had recently claimed to love.
"Well, I kept telling myself... it's a time machine, you can go back whenever and it'll be no time at all to her! But then there was the war, and all the time I kept reminding myself... she's on Earth with no way back here. She can't be dead," he went on. He paused for a moment, as if thinking how he could get his point across, even though he didn't actually have one. "But then... the war ended, and.. she was gone. Telepathic link, you see. And it was silent. I guess I always hoped it was some sort of mistake, and apparently... I was right to hope!" he smiled, looking up at her finally. "So, I guess we've had a few hundred years to catch up on," he laughed softly.
"Does it creep you out, the whole granddaughter thing?" he asked after a pause.