The Falcon in the Barn (Book 4 Forest at the Edge series)

The problem with Shem, Mahrree--with everyone, Perrin concluded--was that they couldn't see what he did.
Shem said his mind was confusing him. Mahrree said it was nightmares. His children said nothing. But he knew the truth: he was surrounded by Guarders, masquerading as cats.
Perrin is right: the Guarders are closing in. But on the edges of the forests another army is assembling, wearing green and brown mottled clothing.
Because they have plans of their own for the wounded falcon in the barn.