Now this is a decent science article. Maybe I should start reading Der Spiegel.
Of course, technically all of us are related to Brad Pitt. And I'm not convinced that, though I have blue eyes, I'm really that much more closely related to Brad than any other Indo-European is.
It is possible to have blue eyes and be more distantly related to Brad Pitt than family members with brown eyes. I'll describe as follows. Brown eyes is a dominant genetic trait. Blue eyes is a recessive trait. Therefore, it is possible for two parents with brown eyes to have kids with blue eyes. This is a child with blue eyes which is more distantly related to Brad Pitt than either of its more closely related brown eyed parents.
You can use the converse to spot illegitimate children, as my old biology teacher done on dull parent evenings. This is because two parents with blue eyes are unlikely to have a child with brown eyes ( http://www.athro.com/evo/gen/inherit1.html ) and certainly not at the 10% ratio observed by my teacher. If you're a fellow with blue eyes and your partner has blue eyes then kids with brown eyes probably aren't yours.
There is a reported 8% children-not-from-their-daddy in western societies.
On a related note, the very first words from most mothers who just gave birth to their husbands is "it looks just like you". Psychology at play: we see what we want to see!
Of course, technically all of us are related to Brad Pitt. And I'm not convinced that, though I have blue eyes, I'm really that much more closely related to Brad than any other Indo-European is.