So that means there are two other Time Lords around the Doctor doesn't sense, bringing into doubt his ability to sense Time Lords these days. Plus, there's uncertainty about the existence of the Master.
The little girl doesn't have to be a Time Lord, since we know the ability to regenerate (and any limitations on it once granted) is somehow artificially given - hence they could offer the Master a new life cycle in both the classic and new series.
Yes, and there's also the issue of fob watches, though the little girl was seen sporting this:
http://ecx.images-amazon.com/images/I/31BDX0BBADL._SL500_AA300_.jpg
Well, that seals it then. She must be a Time Traveller. That franchise didn't begin till 1981. In 1969 a little girl should be wearing a sensible child's timex.