Cancer sufferer Harrington aims to realise 'lifetime ambition' at Aintree
The 76-year-old has won a Cheltenham Gold Cup, a Champion Hurdle and the Champion Chase but conquering the fearsome 30 fences at Aintree and winning the world's most famous steeplechase has been her dream "since she was a child."
Harrington has had very few National runners down the years, 66/1 outsider Magic of Light going closest when second in 2019.
Lifetime Ambition will face 39 rivals, including 26 from Ireland, among them last year's winner Noble Yeats.
There are others who would provide tearjerking stories.
Ain't That a Shame, to be ridden by Rachael Blackmore, and Gabbys Cross go for 2021 winning trainer Henry de Bromhead, whose 13-year-old son Jack was killed in a riding accident last September.
Welsh runner Our Power's part-owner 77-year-old Dai Walters has only just returned home from hospital where he has been since last November after a helicopter crash which also involved the horse's trainer Sam Thomas.
Victory for Harrington, though, would evoke memories of jockey Bob Champion's win on Aldaniti in 1981 after he had come through his own battle with cancer.
Harrington -- who will watch the race at home in Ireland "screaming at the television" as she does not want to risk getting a virus -- says there have been a "few bad days" and "tears" when she was diagnosed last October.
However, she is remarkably phlegmatic about the months since as caring for her 170 horses, of which up to 25 are jumpers, has continued.
"Being able to get up this morning and look at the scenery and horses - I am very, very lucky," she told AFP in a phone interview.
"The kids have been an enormous help but amazingly life went on as normal.
"I have sailed through chemotherapy and in fact I was saying 'bloody hell, everyone says chemo is so bad but I can still do a day's work after a session.'"
'Iconic race'
Harrington -- whose much-loved husband Johnny died of cancer in 2014 -- has availed herself of a present from her children which at first was met with disdain.
"The children bought me a buggy before Christmas and I said 'I do not need that,'" she recalled.
"However, I was getting weaker every day so in the end I was grateful for it as I could go out and look at the horses."
One of those she gazed over was Lifetime Ambition, who has had a decent season running respectably behind some top-class performers.
"The horse is in great form and is aptly named as it is my lifetime ambition to win the National," she said.
"It is an absolutely iconic race. As kids the only race one watched religiously during the year was the National.
"Everyone knew the date it was on and gathered round the TV to watch it."
The National is the immediate goal and then there is another landmark one.
"At the end of this, after my one remaining chemo session, I hopefully will get the all-clear and life will go back to normal," she said.
Harrington has received support from friends in Ireland and abroad, including from her close friend, English training legend Nicky Henderson.
The 72-year-old six-time champion trainer will saddle Mr Coffey on Saturday, his 43rd attempt to win the one marquee race to elude him.
Henderson is admirably honest about his record in the race although he has had two runners-up, Zongalero in 1979 and The Tsarevich in 1987.
"It is as good a chance as we have had in a long time," he told AFP.
"His record is good but mine is appalling. If someone was thinking of backing it they should look at my stats!"
However, if Mr Coffey was to deliver the elusive prize Henderson says no one should expect any announcements about his future.
"I am not going to jump up and announce I am retiring!" he said.