Barbara shrugged gently. "I don't know, you'd really have to ask the Doctor. For all we know you're only around because your mother had a friend of the family called 'Howard', who was gentle and kind, slightly paranoid and overly fond of canned food." She grinned at him. Clearly she was joking.

"Remember that this is a different universe to the one you're from," Barbara continued, bags swinging a little by her side, "you'll still exist but maybe a Howard for this world won't. Or maybe he still will. Maybe he only exists in your universe. I really can't be certain on anything." If only there was a way to call the Doctor.