Nathan does not appear to think this is funny.

"Awwwww, sweetie." The Joker hugs him. "What's wrong?"

"Don't like the idea of her turning. I don't want her hurt bad enough to want her to get to be a vampire out of it."

"Well, what do you wanna do about it?"

"Make sure Kerron knows not to bite humans," says Nathan wryly. "He could already jump high enough to reach a doorknob if he wanted to and we don't watch him twenty-four hours a day. Maybe Milliways will like him as much as it likes Elspeth."

"We could magic him unvenomous, too," he points out with a shrug.

"...I suppose. Just until he's older. It might affect his senses of smell and taste, but female half-vampires get along all right."

Cuddles.

"Love you," he murmurs.

"I love you. So much."

He smiles. "I know, honey."