The Thistle and the Rose (MacPherson Clan, #0.5)

Alternate cover edition can be found here

Desperate Deception
Celia Muir must escape from a burning castle into the Scottish Highlands before English soldiers capture her. With her are loyal friends and servants, all united to protect the infant Kit from unknown enemies. For her clandestine mission to succeed she has to make Colin Campbell, the warrior lord whose help she seeks, believe she is the seductive Lady Caithness.

Irresistible Desire
Colin Campbell's head tells him this Caithness woman is trouble, yet his heart is telling him she is magnificent. Whatever Celia is hiding he needs to know, but he also wants to hold her and kiss her. And as war with England scorches the heathered hills, Colin and Celia find reasons to bare their secrets, surrender to their desires, and head toward a destiny where Scotland's future--and their own--build on the strength of their passion and love...