I think a class in basic human anatomy is in order for the writer for Yahoo! Style who seems to be a tad confused about the location of the Duchess of Cambridge’s knees:
Perhaps if she had looked at some photos on the site she works for she would have seen the location of a hemline and the duchess’s knees:
It looks like the hemline of the coat, at least, is above her knees. So, I’m guessing that her dress is above her knees, too.
Terribly Write 
December 9, 2014 at 1:35 pm
“… has legs for days …” I suspect she’s had them all her life….
But still, it’s an awfully clever way for the Yahoo! Stylists to slip in a bit about the daunting duchess. Back home in England, however, I doubt many would presume to suggest how she dress.
December 9, 2014 at 6:57 pm
I’m sure there are “journalists” all over the world willing to tell the duchess what to wear. But they probably do it knowing where her knees are.