Read the following paragraph and answer the question. Give ONLY the answer, no other words or explanation.

For example:

Answer: <most likely answer, as short as possible>.

Paragraph: Whenever I looked over at the tree across the road , I was haunted by the echo of her screams . My mind filled with the images of what had occured . The colours , the sounds ... I could n't look at the tree without the nightmares coming to me again .

Question: Why do the trees seem to scare the individual ?
A friend died there .
The tree is a reminder of the traumatic event and brings on nightmares for the individual.