The departure of Sue Gray, as Sir Keir Starmer's most senior adviser in Number 10, has shone a spotlight on the role of special advisers in government.    So on today’s Sky News Daily, Niall Paterson is joined by our deputy political editor Sam Coates to find out exactly what role these advisers, often known as SpAds, play in the running of the country.   Niall also speaks to former Conservative special adviser, and author of The Secret Life of Special Advisers, Peter Cardwell, about what it was like to do the job.  Producer: Rosie Gillott Editor: Paul Stanworth