Here's the story.
My wife was born in Peru, according to Peruvian law that granted her citizenship according to Jus Soli, additionally we still have her original passport from Peru. She was adopted by American parents as an infant and became a naturalized citizen when she was 3. We have all the documentation proving this, Birth certificate, Naturalization papers, passports, etc. This all occurred in the early to mid 90's.
My question, does she retain her citizenship to Peru? If her citizenship was renounced wouldn't we have official documentation showing it, issued from either the US or Peruvian governments?