Author Jane shared the news on her Twitter feed with a photo of her and Gerry together. The image, taken in happier times, sees the pair posing together and smiling. In her caption, Jane shared: "My lovely sister, Gerry, passed away at the weekend. Here we are last year when she was in the middle of chemo, but loving the straight wig after a lifetime of curls."
Jane was supported by her fans, with one penning: "Sending my biggest smile and happiest thoughts your way, my friend. I'm so sorry for your loss," while a second said: "I'm so sorry to hear Jane, sending you so much love - thoughts and prayers with you and Ricky."
Ricky, who is currently on tour with his sell-out show Armageddon, typically remains quiet about his family life online.
Despite having been together since 1982, Ricky and Jane have never married, with the comedian explaining: "There's no point in us having an actual ceremony before the eyes of God because there is no God."
The pair are college sweethearts, having first met when they were both studying at University College London, with the couple moving in together after two years back in 1984, with Ricky once joking that their flat was situated above a "seedy sauna".
The pair have also decided against having any children, with Ricky explaining: "Too much hassle. Not something either of us wanted to do. We just ... didn't fancy dedicating 16 years of our lives. And there are too many children, of course."
Jane reflected on their decision in a previous interview with the Guardian, sharing: "I've never regretted not having kids. Even as a child, I found it hard to imagine being a mum. I didn't want to have children because doing so just didn't feel like me. Being a mother wasn't who I was meant to be. Thankfully, my partner, Ricky, felt the same – not that I would make a terrible mother, or if he did think that he thoughtfully kept that to himself, but that he wasn't keen on parenthood, either... We were happy with our decision, and we still are."
The pair clearly have a very strong relationship, with Ricky even revealing on Live with Kelly and Ryan that his current comedy show was inspired by his girlfriend and how he would deal with life if he lost her.
Jane is an accomplished novelist and television producer, having worked on the likes of EastEnders, Teachers and 20 Things To Do Before You're 30. Her book, Got You Back is currently been made into a musical and is expected to debut on the stage next year.
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