The Lost Found (Love's Victory Book 1)

It is halfway through the First World War and Jeanette's son brings home Noah, a boy who says he has come from Belgium with his parents. He is thin, obviously undernourished and his expression in repose is sad. He never invites anyone to his house.
Jeanette becomes very fond of him as he integrates into their family and determines to find out more about him which leads her to Belgium where the war is raging.