When my sister was this age she was terrified of nail polish. For months nobody could figure out why she'd get so upset when some of our good friends (that she genuinely liked) hugged her. After many months I was able to get the reason out of her during a sisterly heart-to-heart. Turned out she was also disturbed by makeup. And, as MumOfThree mentioned, sometimes it was a triple whammy of perfume, makeup, and nail polish that would set her off. (Our mom wasn't big on any of these things herself so I think the unfamiliarity of it was part of the problem.)
