Her character is played by Jacqueline Nairn. Nairn addressed fans on Twitter after her final episode.
"To the Shorty fans, You guys are the BEST! Thank you, with all my heart, for loving the feisty redhead and being so fantastically supportive over the years. I'll miss her too. Love & light always, Jaq x."
Nairn played Wendy on the programme for nearly six years and admitted it was difficult to keep the secret.
"It's been a very long time keeping this secret. So very grateful to have had a job I've loved with all my heart, everyday, for nearly six wonderful years. Thank you, to everyone in the Shorty team at South Pacific Pictures for a fantastic adventure and memories I'll treasure forever," she posted on her Instagram account.
Emotions were running high with Shortland Street fans on Facebook.
One user Rebekah Robinson wrote: "Wendy was everyone's mum.. I was half expecting her to wake up. The poor Coopers have been through way too much."
Another user Emma Stichbury wrote: "What have you done Shortland street, WHAT HAVE YOU DONE!".
- nzherald.co.nz