Both theatre companies, which aim to transform the lives of people with learning disabilities through the arts, were set up in 2005.

The online party will include warm-up routines, dance moves and a virtual blowing out of the candles on a birthday cake.

Simon Morris, general manager at Blue Apple, said: “We are very excited to be teaming up with ArtStream to celebrate 15 years of both our organisations.

“ArtStream is an inspirational organisation that shares identical values with Blue Apple about helping to achieve more equality for people with learning disabilities, who are disadvantaged in mainstream culture in so many ways.

“Both companies support people to develop their personal skills by learning theatre skills and then challenge for more inclusion in the wider world. Like us, ArtStream believes that if people are given more opportunities to show what they can do then they will break the glass ceiling.”