n 1981 a Catholic nun from Singapore began writing letters to a female inmate on death row. It became an exchange that would last seven years. The nun was Sister Gerard Fernandez and the prisoner Tan Mui Choo, a former student of hers who had been sentenced to death over one of the most brutal murders the country had ever seen.
She knew her as Catherine, a “sweet, simple girl” who came from a devout family and attended convent school.
Tan, along with her husband Adrian Lim and his mistress Hoe Kah Hong, were convicted of the ritualistic killing of two young children…more bbc