Something Wild by Linda Davies

We last met her in Nest Of Vipers, Linda Davies' bestselling first thriller about the young city trader turned MI6 agent. Then she was a woman with a host of secrets and a haunted past. Now Sarah Jensen is back again, running from a love which was too big to handle, hiding her baby son from the father who does not know he exists. A woman with more at stake than ever, and more to fear. Something Wild is an absolutely thrilling novel, the story of a woman who was once tough, but is now vulnerable, her skills blunted by motherhood. A woman at bay.
 
- Goodreads Summary