Q: Given a context passage, generate a question from the passage such that its answer is shortest continous span from the passage.
Australian Senator Nick Xenophon said, ''Tom Waterhouse has pushed the envelope to the extent that it has now got to the point that it's out of control and there needs to be a legislative response'' In May 2013, Waterhouse was directed by NSW Racing stewards to keep his bookmaking business clearly separate from the training business of his mother Gai Waterhouse, to avoid public perceptions of a conflict of interest.
A:
Who is the mother of Tom Waterhouse?