|Born||1st January 1992|
|Died||2nd January 1992|
|Sibling(s)|| Steve McDonald|
Liz went into labour when Steve went missing on New Year's Eve. After being born, Katie was placed in an incubator although the McDonalds were told by Doctor Swann that their daughter's chances were not good. They were grief-stricken when she passed away the following day. She was buried a week later by Liz, Jim and Andy; Steve stayed away as he blamed himself for causing Liz's early labour.
Katie had a head of fine, fair hair, despite being premature. Before leaving hospital, Liz was given a photograph of Katie which Jim placed in a silver frame. In July 1993, 11 Coronation Street was burgled and the frame stolen, but the picture was soon found discarded in the ginnel by Deirdre Barlow and returned to Liz.
Liz thought about Katie a lot, especially when she was to become a grandmother. In 2004, Liz disapproved of Steve's decision to play no part in the upbringing of his daughter Amy, and out of gratitude for Liz's support Amy's mother Tracy offered to rename Amy Katherine. Steve's wife Karen felt that Katie had only been brought up to make Steve feel guilty about the part he'd played in her death. Liz also mentioned Katie after Becky McDonald had a miscarriage in 2010 and when Michelle Connor had a late miscarriage in 2017, both times to urge Steve's wives not to let the tragedies destroy their marriages.