Question

Why did mr Oliver feel uneasy when he walked through the pine forest

Answer 1

As the wind blew through the pine forest, it made an unusual hustling sound which gave an unusual eerie feeling. So Mr Oliver feel uneasy when he walked through the pine forest.

Answer 2

When Mr Oliver went near the boy who was sitting alone in the forest to recognise him he felt uneasy as the boy appear to be crying but it was a strange soundless  weeping