The Grand National always comes with a requisite human-interest story and it would be poignant if My Will's owner, Andy Stewart, were to lead him into the winner's enclosure on Saturday.

Punters are pinning their hopes on the nine-year-old, ridden by Ruby Walsh, after the well-backed War Of Attrition was ruled out of Aintree.

But even though Stewart could be days away from his greatest moment in racing, family heartache has meant the National hasn't been at the forefront of his mind.

His 28-year-old son, Paul, broke his back in a snowboarding accident in the winter. Like any father, he wants just one thing. "If My Will does win, I haven't thought about celebrating," said Stewart.

"I'd give up every horse, everything I've got in the world, to see my son get up out of his wheelchair to walk and shake my hand. Mentally he is in good form. He really wants to be there on Grand National day."

The chances of it being a day to remember for the Stewart family rose after War Of Attrition's trainer Mouse Morris decided against running him at Aintree, stating that he was "not 100 per cent happy with him".

"My Will is almost certain to go off favourite now," said William Hill spokesman David Hood.

"Ruby is the most successful Grand National jockey riding today, having won the race twice, and punters remember his recent exploits at the Festival. He's 8-1 at present but I can see him going off at 6-1 or shorter."

Big Fella Thanks, Eurotrek and Cornish Sett will complete a quartet of National runners for Paul Nicholls.

Just as it is for champion jockey Tony McCoy and owner JP McManus, the National remains tantalisingly out of reach for Nicholls. He has saddled 40 runners, with Royal Auclair's second to Hedgehunter in 2005 the nearest he's come to Aintree glory.

But despite the trainer's natural pessimism, Stewart says My Will provides Nicholls with a cracking chance to break the hoodoo. "On Saturday, Paul will be sitting in a corner going, 'I've never won it. I've only ever had a couple that have got round, blah, blah, blah'. The truth is, he's never had My Will in better shape," said Stewart.

"He has been trained for the race for 18 months. We have been thinking about one thing and one thing only: Have we got a racing weight?"

My Will, who shoulders 11st 4lb, was fifth behind stablemate Kauto Star in last month's Cheltenham Gold Cup on only his second outing this season. He previously finished fifth to Madison Du Berlais in Newbury's Hennessy Gold Cup, having returned from a 19-month absence after a leg injury.

His official handicap rating was subsequently revised to a mark of 160, the horse having been rated 152 when the National weights were originally published, meaning he is 8lb better off.

The Stewart family colours will be well represented at the three-day meeting. Big Buck's is out to supplement his World Hurdle victory in the Liverpool Hurdle on Thursday and Champion Hurdle runner-up Celestial Halo bids to upset Al Eile's hopes of winning a fourth Aintree Hurdle on Saturday.

Talented novice chaser Tatenen, who fell when favourite for the Arkle at Cheltenham, is out for redemption in Saturday's Maghull Novices' Chase while Poquelin and Gwanako are in good form for their tests.

But it is My Will and Walsh who are catching the public's imagination.Stewart added: "No French horse has won the National but we'll try and knock that statistic down."