They really were stunningly similar , with a spattering of freckles and a puff of pale hair on their heads . If it was n't for the cut and the expressions on their faces , she would n't have been able to tell them apart . She stood back up .

Question: Why are the two individuals hard to tell apart ?
Answer: The two individuals share similar traits such as freckles and pail hair .The two individuals are   not really doppelgangers ,The two individuals have a very similar cut of hair .The two individuals have almost exactly the same expression on their face .