A search is under way for two lesbian grandmothers who inspired a new children’s book after a chance encounter with a pantomime dame at Blackpool Pride.

The women, whose names are not known, attended a reading by the popular performer Mama G in 2021, complaining to her about the lack of diversity in young literature.

Mama G said she had been reading books to children at Blackpool’s Winter Gardens when the women asked if there were any featuring lesbian grandmothers.

The question left her stumped. “I was like, erm, no. I don’t actually think I’ve ever seen lesbian grandmothers in a story, not even as a subsidiary character,” she said. One of the women, clearly disappointed, told her it was “so hard to find yourself represented in books”.

The conversation prompted Mama G, whose real name is Robert Pearce, to write a children’s picture book where two older queer women are “front and centre for a change”.

The book, The Proudest Bird in the World, will be published on 1 July and Mama G wants to dedicate it to the pair who inspired it – but first she must track them down.

Yet despite weeks of appeals on social media, radio and newspapers, their identity remains a mystery. “I don’t have their names, I don’t even know if they were from Blackpool – they could have been visiting,” Mama G said, comparing the social media campaign to a hunt for a missing person.

The women are described as about 5ft 6in with short hair, one with “salt and pepper loose curls”, and possibly wearing jeans and stripy tops when they met Mama G in 2021.

Despite spending nearly two decades championing diversity in family storytelling, Mama G said the conversation with the women was a “wake-up call”. “These two women are facing an uphill battle when it comes to representation because they’re a minority within a minority and it really stuck with me,” she said.

“Lesbian visibility is considerably less than gay male visibility in just the media in general. The visibility of older LGBT people is greatly reduced from the visibility of LGBT-coded children or young adults.”

A US study in 2022 found that despite a significant increase in the number of LGBTQ+ related books for children since 2000, those characters were rarely the central protagonists and that some groups, such as bisexual people, were “completely absent”.

The Proudest Bird in the World is about an ordinary white bird, Gilbert, who longs to express who they truly are and stumbles upon a Pride parade, where they discover that true colours do not have to live on the outside.

The main characters are two lesbian grandparents who educate Gilbert and their granddaughter on what the colours of the rainbow flag mean to them.

Mama G, who is performing at Edinburgh fringe this summer, said the lack of diversity in children’s books was still a problem, despite the efforts of a number of authors and smaller publishers.

She said publishers told her they “weren’t comfortable” taking on her first book, Oh Yes I Am!, about a boy who lives in a grey world but learns to make it sparkle, because it “could be taken as a LGBT story”.

That book, published in 2023, and The Proudest Bird in the World, were picked up by smaller independent companies.

Mama G said larger publishers had shied away from books celebrating diversity because of their profit margins and that “there’s quite a lot pushback against the community.

“I think to get diverse books published you’ve got to look at smaller publishing houses because they’re in a better position to take a risk,” she said. “I’m excited to see what happens with this book – and I hope that if we do find the lesbian grandmothers, they will be proud to be a part of it.”