Birds of a Feather’s opening credits were hiding a secret about show star Pauline Quirke. From series three onwards the titles famously appeared to feature images of the stars Linda Robson and Pauline as youngsters.

They played sisters in the show and the images show them growing up until it gets to a photo of them in present day, while a recording of them singing What’ll I Do plays over it.

While Linda and Pauline did indeed know each other since they were children, seemingly there weren’t enough pictures of them together in their younger years so the images viewers saw of the younger girls were actually Linda with her real life sister.

Director Nick Phillips made the revelation in a Channel 5 documentary about the hit show entitled Birds of a Feather: 30 Years of Laughs.

“The titles and the credits were very much done on a shoestring, so one of the things I discussed very early on was the recreating the titles and the credits to make them tell a story about the contents of the series,” he recalled.

“I thought there must be pictures of them as little girls somewhere. So I asked Linda and Pauline to bring in their old photos, and in the early stills, you do see Linda and her sister, her real sister, who’s slightly more round faced, playing Pauline as a little girl,” he revealed.

When the photos reach their teenage years it is indeed Pauline in the shots as the pair knew each other many years by then and worked together regularly.

The news will come as a surprise to many who for decades have been certain that all the photos were of the two stars of the show.

One fan who admitted they were shocked by the revelation was former Emmerdale star Linda Lusardi who appeared in the documentary.

“I thought it was them as children in the clip in the beginning. I only found out today that it wasn’t so I was disappointed,” she said. “But they they knew each other from childhood so I think there was a bond there on screen that you couldn’t manufacture.”

The pictures weren’t the only misconception about the credits on the show. The end credits featured what appeared to be home movies of the pair as children.

In this case neither actress featured and the footage wasn’t even vintage but especially shot for the show.

“For the end credits, I cast two little girls to look like little Linda and Pauline. We just took an 8mm camera and filmed them running backwards and forwards,” Nic confessed.

The subterfuge worked though as Nic admittd: “I wish I had a pound that every time somebody said, I love the titles.”