Avery didn't answer Diana, and Evan also looked unhappy. In this situation, Diana became embarrassed all of a sudden.
Evan was annoyed at Diana because she cheated
on him, but he still tried to control himself because she looked fragile.
The doctor also found something wrong. He wrung his hands and explained, "Mr. Howel, I'm glad that Miss. Summer will recover soon, and I suggest she have a rest still, but she insisted on holding a birthday party for you. She said you are the only one intimate relative that she knew here."
The doctor had made an explanation — the reason for holding a party for Evan and her determination.
Avery paid attention to the word "relative" that the doctor said. It seemed like the doctor wanted to justify Diana's behavior.
It was, of course, that Evan and Diana were meant to be a couple, which was not a surprise in The City.