"At the end of it, there were the fireworks, and she flung her arms around me and gave me a big kiss.
"She said 'thank you, that has been brilliant, the best thing so far in my life'. And I thought . . . 'the tickets only cost 20 quid'."
It is now four years since Jasmine – not her real name – came to live with Georgina and her husband Alan at their home in Shrewsbury.
When she arrived, Jasmine was a shy 12-year-old from a difficult background, who found it difficult to show any sort of emotion, but she has blossomed into a lively, outgoing 16-year-old looking forward to university and a dream career in the music industry.
Here is Dame Joan Collins as you have never seen her before, as part of a campaign to raise awareness of the need for foster carers.
Other pictures, which include the late Lynda Bellingham as a teenager in a production of a Midsummer Night's Dream and Christopher Biggins in hippy garb, have been released to mark Barnardo's Fostering Week.
The charity is looking to recruit 500 foster carers in 2015 to help address a shortfall of 8,600 carers nationally.
In the charity's West region, which includes Shropshire, there is a need to enlist 25 per cent more families than at present.
Actress Brenda Blethyn OBE, who is also supporting the campaign, says the work that foster carers do is invaluable.
"They offer vulnerable children and young people a stable, safe and caring home, sometimes for the first time in their lives," she said.
"Although it is a demanding role, it is very rewarding and we desperately need more potential foster carers to come forward for children waiting for a family."
Foster carers must be aged at least 21, although there is no upper age limit, and marital status, gender, sexual orientation, disability and employment status are not a bar to adoption.
Barnardo's chief executive Javed Khan says: "Most of us can remember the advice and support we received from our family growing up.
"Without the right foster family to care for them, many vulnerable children may never experience the kind of love and stability we take for granted.
"Currently a third of all children in foster care are moved between different families more than twice every year due to the lack of suitable foster carers."
Mr Khan says the number of children in the care system in the UK has risen for the eight year in a row to more than 90,000 and at least 8,600 new foster carers are needed in the UK.
"It is a critical situation and Barnardo's is looking for people with patience and commitment to provide a stable home for the most vulnerable children in the UK," he said.
"Fostering is a caring career and I would encourage those who feel they have a lot of love to give to get in touch."
There are tens of thousands of Jasmines all over Britain, and the organisation which manages foster care in Shropshire is looking for more couples like the Halls to provide them with loving homes.
Last year a child was taken into local authority care, on average, once every 15 minutes, and Gareth Walton, operations director for Fostering Solutions, says there are nearly 600 children in the county who need a caring foster home.
He says: "Shropshire district has around 270 children in local authority care who desperately need a safe, nurturing and stable home, and there are 310 in Telford & Wrekin.
"The shortfall in foster carers is only set to increase, with recent reports showing the number of total looked-after children has risen to 68,840, an increase of seven per cent on 2010."
Mr Walton says becoming a foster carer is one of the most rewarding steps anybody can take.
"These children are likely to have had a challenging start to their lives and you can be the person who makes the priceless difference to their life by offering them a home and care," he says. "We want to raise awareness of this need and urge more people to come forward to find out more about fostering."
The Halls first registered as foster carers in 2007, at the suggestion of Alan's sister who had been fostering for some time.
"We did around 18 months of training, and we had two other children before Jasmine who were with us for short periods," says Georgina.
While there have inevitably been difficulties along the way, Georgina says the support provided has been a huge help. And the couple are extremely proud of the progress which Jasmine has made during her time with them.
"When she came to live with us she was quiet and withdrawn, she wouldn't talk, she had no emotions, she was never sad or happy," says Georgina, who is 51.
To add to the difficulties, Jasmine was taken ill with pneumonia during her first year with the Halls, and spent three weeks in Alder Hey Hospital. Months of recovery followed.
But Georgina says that the Jessie J concert marked a turning point, and Jasmine is now a bright, happy and talkative girl.
"She knows what she wants to do, she wants to be a music producer, and she hopes to go to university. We're like a little family now," she says.
The Halls have five children, with 16-year-old daughter Jordan and 15-year-old son Jack living at home.
"We discussed it with all of them, and they all said 'if that's what you want to do, you should do it'," says Georgina. "For Jordan, she loved it, it was another girl who she could do hair and make-up with, and Jack is so laid back it was never an issue."
She does say fostering is not a responsibility which anybody should take on lightly, though.
"You hear a lot of adverts on the radio saying 'you can be a foster parent if you have patience and a spare room', but there is a lot more to it than that. That said, they support you extremely well, they give you training, and during that process you can say at any time 'I don't think this is right for me'."
But the couple say they have found fostering a hugely rewarding experience, and would have no hesitation in recommending it.
Indeed, Georgina has found the experience so fulfilling that she has decided to give up her job as a catering manager so that she can become a full-time foster carer from October.
She says: "As well as Jasmine, I've got two other children of a similar age, so I wouldn't be able to care for any more children while I'm doing the job I'm doing. Because of that, Fostering Solutions are going to be funding me to be a full-time foster carer, and I will be trained in child psychology."