Why does Chris feel guilty when he learns that his mother has been in a car accident?

One day, Chris and his mother arrived at school to find that Chris had forgotten his science paper, his gym shorts, and his trombone. Chris had already been hateful to his mother that morning. Now he pressed her to hurry back to the house and return with his things so he would not get his grades docked. When she told him she loved him, Chris called his mother by her first name, which he knew she hated and did not say he loved her in return.

Chris waited all day, but his mother never returned with his things. It was only when Chris’ father picked him up after band practice that Chris learned his mother had been in a car wreck. Chris worried the wreck was his fault.