she is introduced as katy nelson, the oldest child and only daughter of tommy and angela nelson when they move into no. 6, coronation street. the family had secretly been placed under a witness protection programme, as angela was due to testify in a gangland murder trial. when the brothers of the defendant come to weatherfield in order to kill the harrises, this become common knowledge and the family resume using the surname harris. katy discovers that she is diabetic, and nurse martin platt (sean wilson) helps her to get used to giving herself daily injections of insulin. the pair develop a romantic relationship, even though martin was nearly 20 years older than katy, almost as old as her father. katy becomes pregnant, but her father, tommy, persuades her to have an abortion by fabricating a story that martin was having an affair. tommy hated martin for sleeping with his daughter, branding him a 'pervert.'