Christianne Fortner

Mr. and Mrs. Fortner became the adoptive parents of Johan and Nina after the murder of Mr. and Mrs. Liebert. After a few months, Johan left Nina in their care and ran away from home; they printed several articles in the local newspaper about his disappearance, but their searching was to no avail.

They had decided to tell Nina the truth about her past when she became twenty. However, as the time approached they choose not to do so, deciding to let Nina believe that she was their real daughter. Johan had them murdered by Detective Messener and Detective Muller during the night of the twins' 20th birthday.

(Source: Monster Wiki)