The actor and screenwriter - whose youngest daughter is soap star Gaynor Faye - wrote a string of hit shows during her career, including Band Of Gold and Fat Friends, helping to launch the careers of James Corden and Samantha Morton, to name but a few.
Riley, who starred with Corden and Ruth Jones in Fat Friends, wrote on Twitter: "DEAREST KAY REST IN PEACE……..what a massive shock to hear this news, you have been taken far far far to young. You were the best boss to work for, you embraced all that is good about our industry, believing in talent."
Sir Lenny Henry, who appeared in series three of lottery drama The Syndicate, said: "I was saddened to hear that Kay Mellor has died. I was lucky to work with her on the Syndicate and found her to be incredibly creative , funny and instinctive. She knew what she wanted and knew how to get the best from us as actors. She will be missed. Condolences to her family."
Kay Mellor directing on Syndicate 3... pic.twitter.com/YVfaTnyYeh
— Lenny Henry (@LennyHenry) May 17, 2022
I'm A Celebrity winner Danny Miller, who worked with Faye on Emmerdale, tweeted: "Devastated to hear of the passing of Dear Kay Mellor. An incredible talent in the TV world and someone who always had a warming smile on offer with open arms. Sending all of my love to Gaynor and the rest of the beautiful family during this difficult time."
Former Emmerdale star Hayley Tamaddon said: "Such sad sad news about the wonderful kay mellor.. She was always so lovely and kind to me.. a truly brilliant lady. My thoughts and love and strength to @MsGfaye and all her family at this difficult time."
Corrie's Antony Cotton said: "I’m totally shocked to hear that Kay Mellor has died. I can’t imagine how her family feel. Devastating. She was a real trailblazer for women in this industry. Rest In Power, Kay."
Comedian and actor Josie Lawrence wrote: "Oh no. So very sad to hear about Kay Mellor. A fantastic writer and wonderful woman."
Playing The Field's Sunetra Sarker said: "Devastated to hear of the passing of one of Britains finest female writers.I admired & respected #KayMellor immensely. I remember how comfortable she made me feel when I worked with her, so clever and witty. From the iconic Band of Gold to present day she truly championed women."
Soap star Chris Fountain tweeted: "Heartbreaking to hear about the passing of Kay Mellor. A wonderful woman, magnificent writer and a force of nature. I consider myself very lucky to have worked with her. She gave me a chance when many haven’t and I’ll be forever grateful for that. Rest in peace Kay."
Emmerdale's Michelle Hardwick said: "So so very sad to read the news about the incredible Kay Mellor. She produced some of the best dramas of our time. Was so lucky to meet her on many occasions. My thoughts and prayers go out to all her family."
And Loose Woman Sherrie Hewson tweeted: "There are no words I can find about the passing of the incredible Kay Mellor. So lucky and honoured to have worked with her . Such talent , such passion, so funny. Never to be replaced. Big love to all her family at this time."
Leeds-born Mellor began her career writing plays, worked on Coronation Street and created the award-winning children’s drama Children’s Ward.
She went on to pen critically acclaimed crime drama Band Of Gold, about a group of women from Bradford’s red light district, starring Morton. And her Bafta-nominated series Fat Friends, about a slimming group, brought together Gavin and Stacey stars Corden, Jones and Alison Steadman.
Jones told the PA News Agency: “I am completely shocked to hear the news of Kay’s untimely death. Her contribution to British television was outstanding and I feel privileged to have worked with her.
“Such a down-to-earth, funny, big-hearted person whose brilliance lay in seeing the extraordinary in the day-to-day. She was a great mentor to me when I first started writing – and always hugely encouraging of new writers – a real testament to the idea of paying it forward.
“British television has lost one of its greats. Thank you Kay for all that you gave us. I cannot believe you’ve gone."
Mellor also wrote BBC One’s women’s football series Playing The Field and more recently Girlfriends, starring Phyllis Logan, Miranda Richardson and Zoe Wanamaker on ITV.
Mellor received an OBE in 2010. She and her husband Anthony were married in 1968 and have two daughters, actor Faye and television producer Yvonne Francas.
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