ㄏㄨㄢˋㄋㄢˋhuànnànㄐㄧㄢˋjiànㄓㄣㄑㄧㄥˊzhēnqíng

患难见真情
  1. 危險困苦處境才能真切感情 患難見真情日久見人心」。

a friend in need is a friend indeed (idiom)​
Not (S)​, amicus certus in re incerta cernitur; a friend in need is a friend indeed