"I shall," Jareth assured her, "when the time comes." When the time would be, he wasn't certain. There wasn't any really good way to tell her the kind of things he had to tell her, and half of the battle was convincing himself of it before he could even do that. He noted with some satisfaction her quick agreement on the baby's new label. Intriguing. He had expected a fuss, or maybe some insistence that they call the baby Hoggle or something equally ridiculous.
However, she was being obstinate, or purposefully dense. Did she not understand what he meant when he told her things like that? He wasn't just spouting out the same old you-are-destined-to-be-my-queen speech, he was trying to tell her that he cared about her. Not trying to make a point or remind her of her destiny.
"You misunderstand me," he said, carefully trying to avoid the appearance of annoyance (although it certainly was there at the back of his mind). "I didn't intend that in the sense that you're important to the Underground. You are. But what I intended was for you to understand how important you are to me. Personally." There, that was all he was going to say about the matter. If she didn't recognize endearments when she heard them, that was most certainly not his problem.