Is it possible to change a single page to a regular page-type without loosing sub-pages? eg. if I start with this:

|- Contact us (single page)
|- London (single page)
|- New York (single page)

And I want to change to this:

|- Contact us (page type)
|- London (single page)
|- New York (single page)

Can I do it without deleting 'Contact us' (and consequently all sub-pages) then re-creating all 3 pages?

Thanks
Joe