Rhodes made the comment when CNN's Christiane Amanpour asked her this week if she is excited about the new addition to the royal family.
"Not terribly," she laughed. "Well, you know, everybody has babies, and it's lovely. I don't get wildly excited about it."
"Really?" Amanpour asked. "Not even for the next heir to the throne? History?"
"Yes, all right, I'm prepared to be excited," Rhodes said.
William's wife Kate Middleton reportedly was due to give birth to their first child July 11, but the palace hasn't confirmed her due date and the baby has yet to arrive.
NBC News said Middleton's mom, Carole, has told friends the child will be a Leo, an astrological sign whose dates don't begin until July 23.
Middleton also has been spending time at her parents' country house -- miles from the London hospital where she intends to give birth -- suggesting she's not expecting her baby until next week, Zap2it.com said.
William is the queen's grandson.