Popsugar Celebrity The Royals Signs You're Obsessed With the Royals You Know You're Obsessed With the Royals When . . . . September 29, 2015 by Annie Gabillet View On One Page Photo 6 of 21 ADVERTISEMENT () Start Slideshow Share This Link Copy ← Use Arrow Keys → 6 You know who Prince William's flames were before Kate Middleton. Looking at you, Isabella Calthorpe, who also happens to be the half sister of Prince Harry's ex-girlfriend, Cressida Bonas. Previous Next Start Slideshow The RoyalsKate MiddletonPrince William