She studied English, Zoology and Botany at St Andrews University before becoming a public protection scientist.
[3][4] McKay says of herself as a child "I anaesthetised myself against the big bad world with large doses of literature.
"[5] The Casson Family series comprises the Whitbread Award-winning Saffy's Angel (2001) and four sequels: Indigo's Star (2004), Permanent Rose (2005), which was shortlisted for the 2005 Whitbread awards, Caddy Ever After (2006), Forever Rose (2007), and prequel Caddy's World (2011).
The books have been published as audiobooks, with the first two read by Nigel Lambert, The Amber Cat also by Ron Keith, and Dolphin Luck by Judy Bennett.
Dog Friday has been adapted into a German film, Ein Hund namens Freitag.