Separated at birth?

Something which I've started doing recently is taking more photos - I realised that there are long periods of my life that I have no particular record of and snapping away merrily seems easier than keeping an actual, proper diary.
Looking through recent pictures I came across one of vulgarcriminal, and stood in amazement.
"By George!", thought I. "She looks like someone famous!"

Boris:


Tiffany:


One is the flaxen-haired scourge of left-wing idiocy, and the other is MP for Henley-on-Thames.

Could they by any chance be related? I think we should be told.*

^{*This is actually the most unflattering picture I've ever seen of Tiffany, who is in reality astonishingly good-looking.}