William & Kate Running The London Marathon? (VIDEO)

The Duchess of Cambridge may have to strap on her sneakers yet again -- Catherine and her prince may be running the London Marathon!

OK, maybe not. But if Kate's brother-in-law has his way, the royal couple would be sweating it out through the 26.2 miles in 2013. Prince Harry spoke to the BBC at this year's race, praising the competitors and their charitable efforts. Of course he was asked by the BBC's Sue Barker, "Do [the other runners] ever persuade you to have a go?"

"I've been trying to get a place [in the race] for years!" Harry sarcastically quipped. "I can't get myself a place. What do you have to do? But no, what's fantastic is that my brother and his wife will be doing it next year, I think," he giggled. "He's going to have to now, isn't he?"

"You've said it live on-air now, exactly!" joked Barker.

As awesome as it is to imagine, can we really picture Kate crossing the finish line in her L.K. Bennett wedges and that glossy brown hair in a mess? Yeah, not so much. Pippa, however, would be a natural.

Watch the prince's interview at BBC.co.uk.