Shadow by Michael Morpurgo

Shadow, set partly in Afghanistan,
partly at Yarl’s Wood immigration
removal centre in the UK, is the story
of Aman, an Afghan boy fleeing the
horror of war. Told in his own words, it
traces how Aman befriends a western
dog which appears outside the caves
where he lives with his mother. When
Aman and his mother decide to make a
bid for freedom, the dog, which Aman
has called Shadow, will not leave them.
Soon it becomes clear that the destinies
of boy and dog are linked.