how do we know that peter is unhappy. number the stars

In the book "Number the Stars" by Lois Lowry, there are several indications that Peter is unhappy:

1. In Chapter 7, Peter's hand is described as "tension-knotted," suggesting that he is anxious and stressed.

2. In Chapter 12, when the resistance group is moving Ellen and her family, Peter's face is described as "grim and hard." This suggests that he is burdened by the dangerous situation they are facing.

3. In Chapter 14, Peter admits to Annemarie that he feels helpless and frustrated because he wants to fight against the Nazis but can't.

4. In Chapter 16, when Peter and Annemarie are captured by German soldiers, Peter's expression is described as "miserable." This shows that he is deeply unhappy and scared.

5. Overall, Peter's behavior throughout the book, often appearing serious and worried, portrays his unhappiness and the weight of the events he is involved in.

Note: The book "Number the Stars" does not explicitly state Peter's emotions, so these observations are based on the descriptions provided by the author.