Fussy dresser

My 9 year old daughter, has had issues on and off for years, with the seams in socks and her underwear giving her (excuse the wording ) wedgies. She goes threw and tries on at least ten pairs of either before she makes up her mind about which are more comfortable. Because she is quiet skinny i find that the part of the knickers that go through between her legs are to wide, and have tried searching for thinner ones and have had no luck, have even tryed boy leg's no such luck as she does not like them either.. if any body has any idea's or suggestions i would love to hear them.. thank you.