Nine-year-old Grace, of Eldwick, Bingley, has a life-limiting condition called Niemann-Pick Type C and has an on-going appeal in her name.
And while she has a twin sister Emily who is unaffected and she also had a brother Harry who lost his fight against the same condition when aged seven.
The day of the Great North Run falls on what would have been Harry's 11th birthday.
"Martin House has supported Harry, Grace and Emily and her family from the day that the disease was diagnosed," said family friend Jane Chapman, a teaching assistant at Ben Rhydding Primary School, Ilkley.
"It is a place where the family can visit every now and again, to be cared for by amazing, wonderful people, a home from home which allows them to recharge their batteries. Please help us to support these fantastic charities."
She and Hester, an office worker at the same school are both members of Baildon Runners club and have taken part in the the Great North Run several times before.
Niemann-Pick Type C is a condition which eats away at the brain's control of body functions. It affects only about 50 children in the UK
Grace's parents Carl and Fiona Hitchens have given up their jobs in the computer industry to care for her.
Last November they started an appeal called Grace's Wish to raise £12,000 so she and her twin sister can swim with dolphins in Florida while she still can - and pay a visit to Disney World as well as to provide her with a specially adapted bike and support Martin House hospice and Niemann Pick-UK .
So far the appeal has raised more than £20,000 and they hope soon to be able to take their daughters to Florida.
Mrs Hitchens said: "We want to fill her life with joy, as she does ours, and let her live life to the fullest while she can.
"My baby girl gets up every morning and greets us with a smile on her face. Whatever life throws at her, she carries on smiling and brings happiness to everyone, she enjoys every moment."
The family are continuing to fundraise to support the charities.
To sponsor Jane and Hester, visit www.justgiving.com/Jane-and-Hester.