I have brown hair unlike my sister who is blonde
I also have a dark brown hair. Brown hair is actually the second most common color, of black being first.
yes.  it is strange - I wonder where red hair comes from
Brown hair is this shade due to having high levels of the dark pigment eumelanin, and lower levels of the light pigment pheomelanin.
Yes it is interesting how certain countries tend to have more of certain hair colors
True. Brown hair is more common in the Western World. Mainly in Europe, the US and some areas in the Greater Middle East.