ANEW arrival in a family dynasty that has already delivered three Commonwealth Games gold medals and seven in all suggests it may soon be time to pen another chapter in the McIntosh shooting legend.

Mother Shirley and father Donald represented Scotland at the Commonwealth Games. Shirley claimed four medals: no Scottish female competitor in any sport has won more. Donald also made the Games team, having won two Commonwealth Championship titles. He has been Scotland's coach at two Commonwealth Games and will be team manager in Glasgow this year. As Britain's head rifle coach, he was with Team GB in London.

Their elder daughter, Jennifer, returned from the last Commonwealth Games with two gold medals (including in the event which mum had won) plus a bronze: the best haul by any Scottish woman at a single Games. But none of her Commonwealth disciplines was in the Olympics. Undaunted, she switched to air rifle and made the team. She is already pre-selected for both air rifle and three-position smallbore at Glasgow 2014 and, now, her sister Seonaid, a 17-year-old Dollar Academy schoolgirl, has also achieved the Commonwealth air rifle qualifying standard.

On Sunday at Glenrothes, in the Scottish Grand Prix, Jen narrowly denied her sister the air weapon title by 613.8 points to 613.5. "It's the smallest margin there's ever been between us in a qualification round," confirmed Jen yesterday. "Shooting is one of those sports where you can't really push anyone. I just get on with it and shoot my match, as I always have. The same was true in the final: I just focused on what I was doing and didn't worry about anyone else. In the end that worked out just fine for me.

"When we're on the range, she's just another competitor. I have always demanded the very best from myself so [having] her competing alongside me doesn't really change anything for me. As a sister, I'm delighted for her to have qualified and will be incredibly proud of her should she be selected."

Jen's coach, Sinclair Bruce, commends her focus, discipline and maturity. "She is a different athlete to the one I first worked with eight years ago," he said. Finishing only 42nd in the Olympics was hard to take, "but it will help her in going into a home Games in Glasgow as favourite".

She has recovered enough to confide that three medals in Glasgow is only part of her personal goal this year. "But it took quite a while to come to terms with London," she said. "I've only really started to feel like my old self now, and it's amazing. If my experience from London has taught me anything, it's to relish the good times and make the most of them, because they don't last forever.

"Dealing with my own disappointment wasn't easy. I knew I wasn't a medal contender when I went in to the Games but I also know that I have the ability to perform when it really matters, so I guess I'd hoped that it would have gone better than it did. Being ill didn't help and I think that prolonged how long it took for me to deal with my disappointment; every day was a reminder of why I'd failed, in my eyes."

Having witnessed this angst, mum discusses the promise of the baby of the family with reticence. The Glasgow qualifying window remains open until mid-May and, with Jen already pre-selected, at least four women are chasing the remaining place. Thus far, though, Seonaid is the only one eligible for consideration. This, just 18 months after having taken up the sport, and barely four in the national squad.

"We don't want to jinx anything," said Shirley, "and we don't want to put too much pressure on her. One reason why Seonaid didn't start shooting until recently was the expectation that people would put on her because she's Jen's sister. But on her own terms she decided she wanted to start shooting air rifle, to see if she could do it to an appropriate standard. She has come up pretty quickly."

It all began when Shirley shot with her uncle's air rifle in the garden as a child, before a more formal introduction through the cadet corps at Dollar Academy and then the University of Edinburgh where she met Donald. He had been taught from the age of 12 by his own father, who shot for Scotland more than 30 years ago.

The sport has changed dramatically since Shirley won Commonwealth gold and silver in 1994, and double bronze in 1998. In the early 1990s, the 10,000 rounds she shot annually cost £1200 a year. Economics dictated that some preparation was dry firing - shooting without ammunition - on the floor in their Edinburgh home while Jennifer slept in her cot. Donald would do the same after hours in the boardroom of the software company where he worked. It was the only room big enough. But the pair could not chase their competitive targets together.

Today, Jen fires some 15,000 rounds (it costs nearly £3000 annually at retail prices). As a GB team member, ammunition is sponsored, while her father's shooting equipment company, Edinkillie, sponsors her clothing. Jen's fiance, the former Scotland squad shooter Andrew Ross, works there.

Dry firing remains a valuable coaching tool because the development of computer software permits precise analysis and feedback. Adaption for live firing has raised the bar further and it is now in routine use at the range at Meadowbank stadium, which reopened late last year.

The outcome has been a global rise in standards. Twenty years ago, perhaps six people were truly competitive for Olympic medals. Now it is often upwards of 30. In Scotland it is reflected by McIntosh, the Commonwealth champion, being one of six women who have shot the 2014 qualifying mark in smallbore prone. There are just two available places and she has yet to be selected.

Donald and Shirley used to train at Meadowbank but the army withdrew the licence on safety grounds more than 20 years ago. Donald has been the driving force behind its restoration, bankrolled by sportscotland. "The wall wasn't strong enough to be sure an accidental discharge would not escape the building," he said. Reopening Scotland's only indoor 50-metre range is a major achievement; it is a busy home for the sport, developing critical mass and new enthusiasm.

Shirley had a couple of years of Lottery support before Kuala Lumpur in 1998, but the couple had to stagger their careers. "We were young and didn't have a big income," said Donald. "It was not feasible for both of us to shoot at the highest level. With the Lottery now, it's chalk and cheese. The support we get - money to run programmes, put coaches in place, run training camps and competitions, all that support from the sportscotland institute of sport - it's fantastic."

Shirley, an accountant, becomes frustrated when she competes: "I have to keep reminding myself I do it for fun now. I don't train. But watching the girls is 10 times worse than competing. I'm incredibly proud of both of them. I look at them and think, 'where did they come from?' And part of the time I look, and feel old."

Having his daughter on the team can be "emotionally challenging", admitted Donald. "There are days when you get a bit tense. I plug in my iPod. Music preserves my sanity at competitions."

Jen's next contest is the European air rifle championship at the start of next month in Moscow. Glasgow 2014, and the World Championship in Granada, are her other priorities. Her sister could yet join her in Glasgow and Spain, where there is a world junior event.

"Ideally I'd like to qualify for a final at the Europeans next month," said Jen. "As for the Commonwealth Games, I'm targeting three medals from three events, and I'm aiming for a top-10 finish at the World Championship in September."