Nolan and her four sisters, who were a successful pop group in the late 70s and early 80s, have supported the Alzheimer's Society for more than a year. Their mother has an advanced form of the disease, needs round-the-clock care and can no longer recognise her own children.
In a recent interview with the News of the World, Nolan said: "It's been heartbreaking. It's such a cruel disease. I wouldn't wish it on my worst enemy."
Later this month, Nolan and her partner, Ray Fensome, will cycle 400km along the banks of the Nile in Egypt to raise money for the society.
Last year, the Nolan sisters all took part in a march to Westminster as part of the charity's continuing campaign to get better treatment made available on the NHS for Alzheimer's patients.
Maria McDonagh, celebrity coordinator at the society, says: "Coleen understands all the issues and knows the often harsh realities of caring for a loved one with Alzheimer's. There's no substitute for that."
Girls Aloud and Sugababes are teaming up to release a single on 12 March in aid of Comic Relief's Red Nose Day
The rival girl bands have produced a remix of hit single Walk This Way by rappers Run DMC and rockers Aerosmith.
The video that comes with the single shows both bands paying homage to the original rap video before a showdown between them takes place on the catwalk.
Red Nose Day takes place on 16 March and this year's theme is The Big One. Members of the public are being encouraged to wear over-sized clothes to complement this year's larger red noses and raise money for Comic Relief.
Cheryl Cole from Girls Aloud said: "It's amazing to think that the money raised from this single will help transform the lives of people living in really difficult situations."
Shilpa Shetty, the Celebrity Big Brother winner, is setting up a charity to tackle Aids in India, her home country. The Bollywood actress announced her intention on her recent trip to the House of Commons. The charity will be called the Shilpa Shetty Foundation. She said: "Aids is a subject very close to my heart. India has the second highest number of Aids sufferers in the world."
Tracey Emin, the controversial British artist, will clean the house of the highest bidder in an auction at the annual Lighthouse Gala to raise money for the Terrence Higgins Trust. Other lots include a tour around the set of Coronation Street with actor Anthony Cotton, who plays Sean Tully in the soap opera, and a chance to walk your dog with former Spice Girl Geri Halliwell. The auction will take place at Christie's in London on 12 March.
Preacher Moss, the US Muslim comic, is one of the stars of a comedy tour organised by Muslim Aid that aims to use humour to break down cultural stereotypes. The Allah Made Me Funny tour starts in London on 7 April and will visit cities across the UK, including Cardiff, Manchester and Bradford. Moss said: "Through humour we are able to play with stereotypes and demonstrate that laughter is universal."
Neil Finn, the lead singer of rock band Crowded House, performed at a concert to raise money for Scope at Stowe School in Buckinghamshire earlier this month. It was followed by an auction featuring lots donated by celebrities including singers Sir Elton John and Kylie Minogue.