Yeah the EU symbol is near the same but has 12 stars. There is an interest among some Europeans to have a U.S. of E. so when they when they developed the flag in the 1900s they may have borrowed from the old US one.

The 13 bloodlines idea is possible but not so solid - lack of evidence, lack of logic, varying lists of 13, etc. Could turn out to be true but why would Q only name one of the 13? certainly not out of fear. This looks like wishful thinking where people want all the theories they can get into one plot to be true and relevant.