When most people think about 79-year-old grandmothers, they imagine someone who bakes, knits and enjoys Countdown in the afternoon.

But Vera Amys, 79, from Watton, who has four children and eight grandchildren, will be falling 12,000ft from a plane in a tandem skydive at Beccles airfield this Saturday for Autism Anglia. The reason for this brave activity – to raise money for the charity which has supported her 47-year-old autistic daughter, Helen Broughall, for more than 20 years.

Joining Vera, a retired auxiliary nurse, will be her daughter Caroline Wheeler, 41, from Holme Hale, her grandson Joe Weatherill, 26, from Carbrooke, and her future daughter-in-law Lois Ware, 30, a care assistant, from Watton.

'I'm a bit nervous, but excited,' Vera said. 'Autism Anglia is brilliant. We are thankful everyday that Helen has got a lovely home.'

Caroline, a customer consultant at Watton's Norwich and Peterborough branch, said: 'I'm so proud of my mum. She is very determined to do it and we are giving something back to Autism Anglia, which has given Helen and us so much support.

'I'm in awe of mum. To do something like this at the age of 79 years old is amazing, but knowing her it doesn't surprise me. She has never been a typical grandmother sitting in her rocking chair and knitting.'

Helen first moved into Whitstone House care home in Norwich Road, Dereham, 26 years ago, which is run by the Autism Anglia, previously known as the Norfolk Autistic Community Housing Association.

A few years later she moved to Walnut House, which was built on the grounds of Whitstone House, and allows people with autism to live together and carry out general household chores while receiving 24-hour support from a carer.

Helen also spends time at Dereham Day Services on the Rash's Green Industrial Estate and every third weekend at home with Vera or her father Rod Broughall, 79, from Watton, who are separated.

The group hopes to raise �500 and if you would like to sponsor the family either donate money at Watton's Norwich and Peterborough branch on the High Street or visit www.bmycharity.com/carolinewheeler, www.bmycharity.com/joeweatherill or www.bmycharity.com/loisware