The Phantom Feud (Death's Dragon Book 2). Death's Dragon, #2

Adi has decided to remain in the Land of Shadows and help fight against the monsters that seek the sacred item hidden in those dark woods. Her choice is soon put to the test when more trouble creeps into Death's domain. That problem comes in twos as Adi learns about the southern Points of the pentagram where two of the Keepers have kept up a bitter feud. The source of the problem lies deep in the past, so Adi and Duncan must dig through the skeletons, sometimes literally, to purify the bad blood before the feud leads to the downfall of the entire realm. Adding to the problem is the appearance of a young puppy.
The wriggly creature wandered through the Veil and winds up in Adi's unwilling arms. Now she has to babysit the unexpected visitor while helping Duncan to fight against savage monsters, fighting Keepers, and a mysterious shadow lurking in the background of all their troubles.