Who are you related to?
Here is an interesting video - that shows a girl who showed how Barak Obama was related to many of the US presidents (thrpouigh his white maternal ancestry)
https://www.youtube.com/watch?v=uw2mkHmIKOA
if we go back far enough - we are related to virtually everyone.
Most people who have British Ancestry - are not only related to each other - but also related to English royalty.
Its just a matter of matehmatics - the farther you go back - the more ancetsors you have - millions of them.
with everyone having so many ancestors - the farther you go back - the higher the probabilty that two people are related.
https://www.youtube.com/watch?v=mnYSMhR3jCI
applications like Relative Finder - use this mathematical novelty - coupled with the massive FS database - to show how we are very very distantly related to many people . . .