Tracy Hogg, the British nanny who scored a big hit with a series of Baby Whisperer books at Ballantine, is moving to Atria with a very large two-book deal signed by another Tracy, editorial director Tracy Behar. She bought world rights from Eileen Cope at the Lowenstein/Yost agency for Super Secrets of the Baby Whisperer and a second book, to be co-written, like earlier ones, with Melinda Blau. The first book, which will deal with questions anxious mothers have brought up on Hogg's Web site as well as at her national appearances, will be out in 2005, the second a year later. Super Secrets will cover problems connected with infant sleep, eating and emotional stability, among many other topics.