✔ 最佳答案
身世之謎:the mystery of one's family background
實例:
She comes to England to see the place, ... and to find out more about the mystery of her family background.
她來到英格蘭造訪那個地方... 也去設法多了解她自己的身世之謎。
http://www.goodreads.com/book/show/6316158-tainted-tree