Celia Stewart is a fictional character from the Australian soap opera Home and Away played by Fiona Spence. She made her first screen appearance during the episode broadcast on 26 January 1988. The character is portrayed as a gossiping busybody and spinster who occupies her time with the Presbyterian church. In her early appearances, she formed an alliance with Donald Fisher (Norman Coburn) and, though she has conservative views, she is not malicious. After one year as Celia, Spence hoped that she would find romance and change her attire. Producers decided to implement change and added smart outfits to the character's wardrobe. Spence decided to leave the series in 1990 and Celia departed the same year. She has since reprised the role on four occasions. After carrying out missionary work in Africa she returned to Summer Bay in 2000, 2002 and 2005. In 2012, it was announced that Spence had agreed to return once again. Originally heralded as the chance for Celia to reconnect with her on-screen brother, Alf Stewart (Ray Meagher), it was later revealed that she was hiding a shameful secret.

Spence's casting in the serial was publicised in the 9 January 1988 issue of TV Week. Writer David Brown said Spence had been cast in the major role of "town busybody" Celia Stewart. It marked Spence's television comeback, after she previously starred in Prisoner as Vera Bennett from 1979 until 1981. Spence returned to her native Sydney for filming, after eight years away, and she said she was looking forward to another regular television part. She told Brown "The series has a lot of charm and warmth. It's also good to be working on a series from day one. I remember the same feeling on Prisoner because I was also there from the beginning." Spence was also "eagerly" looking forward to playing her new character, and Spence said Celia was "so different. She's very vulnerable, unlike Vera."

"She's well-meaning but tactless. She's pretty gossipy and a bit bigoted. She's very interested in everyone else's life because she really doesn't have one of her own. She's going to be really interesting to play. There's quite a touch of snobbery there."

— Spence on Celia (1988)

In the Home and Away Annual, Melanie J. Clayden wrote that Celia "loves to gossip and can be a real busybody". Celia "must be regarded" with sympathy because she is a "lonely spinster with nothing but the Presbyterian church to occupy her time". In the Annual written by Kesta Desmond, she was described as the youngest sister of Alf Stewart (Ray Meagher), but "unlike him she has never married" which turned her into the "stereotypical spinster" and "keen church goer" with a "bitter life". In the book Home and Away Special Celia and her older sister Morag Bellingham (Cornelia Frances) are described as being "two sides of a coin". Celia is "quiet and conservative", which contrasts with the "ruthless" Morag. Andrew Mercado wrote in his book, Super Aussie Soaps, that she was a "prudish" character. She has also been described as a "bitter spinster" and the "town gossip".

Celia was similarly described by the serial writing team as, "the town's busy-body spinster, bitter that love has passed her by and taking that bitterness out on the world." She is a "major ally" to Donald Fisher (Norman Coburn) and loves to gossip because it "helps fill her life". Despite these traits, there is "not a malicious bone in her body". In the book Home and Away: Behind the Scenes, Spence told James Oram that Celia is very different from the character she previously played on Prisoner. Unlike Vera Bennett, Celia is "very vulnerable". Celia is involved a comedy storyline in which locals search for the Summer Bay bunyip. Spence said that her funniest night shoot occurred while filming Alf cooking bunyip burgers and Celia selling tea towels.

She also revealed that there would some changes to her character. After one year in the series, Spence had hoped that Celia would find a man and dress better. Home and Away's writers then informed Spence that they would make those slight changes. She told Oram that "there's a touch of romance that will be wonderful for Celia and there will be a remarkable change in her appearance. Celia will be going on a shopping spree to buy some rather smart outfits." Other than Spence, Celia has been portrayed by Gilda Ferguson, Tatham Lennox, and Annie Buckley in flashback sequences.

"I am absolutely delighted to be back in Summer Bay! I have never turned down an opportunity to bring Celia out of mothballs; she is a great character and I love playing her. I’ve just adored playing her. She has always been such a fun character so, I’ve enjoyed many story lines.