What does sympathetic mean why wasn’t Jamie being sympathetic

In context, sympathetic would mean kind..... considerate. Jamie wasn't being sympathetic because he ran away screaming when he saw August.... because he continued to do so even later in his kitchen.

“It wasn’t a scream,” argued Jamie. “It was like an ‘Ahhh!’ ” He put his hands on his cheeks and started running around the kitchen.

“Come on, Jamie!” said Mom angrily. “I honestly thought both my boys were more sympathetic than that.”

“What’s sympathetic?” said Jamie, who was only going into the second grade.

“You know exactly what I mean by sympathetic, Jamie,” said Mom.

“It’s just he’s so ugly, Mommy,” said Jamie.