Gabby's gift: Auckland woman's tragic death saves six lives on her 20th birthday

It was supposed to be a fun night with her friends celebrating her 20th birthday - and when Gabrielle Marsh started to get a headache, no one suspected she would be dead hours later.

Photos of the night show the young Auckland woman raising a toast with her best friends, showing off the platter of food she'd thoughtfully planned and created for the night.

Two hours after those photos were taken Gabby, as she was known, was lying on the floor of her Avondale home in agony, her mother Kathryn at her side and an ambulance was on its way.

Later that night as Gabby lay hooked up to life support machines Auckland City Hospital staff delivered the heartbreaking news to her family - she had suffered a brain hemorrhage and was unlikely to survive.

The next day a decision was made. Gabby was to be taken off life support - but not until her organs had been donated.

And on Monday March 6, on her 20th birthday, after her family had said their goodbyes, Gabby was taken to surgery and her organs were donated.

"The woman at the hospital called me and said it was all done, and the donation was taking place as we speak," Kathryn Marsh told the Herald.

"Gabby loved doing things for other people, and that was her biggest, most amazing gift."

Gabby's organs saved the lives of at least six people; her kidney, pancreas, lungs, liver and heart valves were all successfully donated.

"Of course, more than anything, we would love to have her here, but that's not to be," said Kathryn.

"But if anything good can come out of it, if she has helped people, then that's comforting."

Gabby was the eldest of three children and is survived by Jacob, 18 and 16-year-old Victoria.

Her death was the second tragedy for her family, her father Shayne died just 17 months ago after a long illness.

"It's still not really sunken in, it was so sudden," Kathryn said.

"Shayne was sick for 14 months and we all had time to get used to the idea, but with Gabby it was the complete opposite. It's left us all a bit shellshocked."

Gabby was born and raised in Auckland, attending Mount Albert Grammar School before enrolling at Auckland University.

She was about to start her third year of a double degree in commerce and law when she died.

"She was a really good sister, she was kind, generous and she was like a second mum to me," Jacob said.

Her family described her as extremely thoughtful and loving, adventurous, caring, a "rock star academic" and a young woman motivated and driven with a lot of energy.

"She had a killer smile that came easy and often," her aunt Michelle Cliffe said.

Kathryn said she didn't know where to begin when asked what was special about her eldest child.

"She just made people feel at ease and she was easy to be around. There was something special about Gabby," she said.

After Shayne died, Gabby was a "phenomenal help" to Kathryn, stepping up to do her share of cooking, cleaning and helping with her siblings.

"She just got stuff done, she was pragmatic, hard working and so organised," Michelle said.

The day Gabby died she woke early and went for a walk with Kathryn - something they did most days together.

Then the pair went to Newmarket shopping and Gabby helped her mother choose a new swimsuit for an extended family holiday to Fiji in April.

The family ate lunch together and Gabby went to watch her boyfriend Bradley play softball before returning home to prepare for her party.

She didn't drink alcohol, but prepared pina colada cocktails for her three best friends, making a rum-free version for herself.

The girls had planned to go out in the city that night; Gabby loved old music so wanted to go dancing at Irish bar Danny Doolans.

Bradley was going to pick them up and drive them to town.

Then, Gabby started to complain about having a headache.

"It was getting worse and worse," Kathryn said.

"She just wanted to lie down. Her friends left, they told her it was okay, that they would celebrate with her another time and they called Bradley to tell him."

After the girls left, Gabby started throwing up and became agitated and slurring her words.

Kathryn suspected a severe migraine, and called 111.

As the paramedics arrived - and Bradley - Gabby lost consciousness.

She never woke up.

Doctors have told her family they believe she had a arteriovenous malformation (AVM), a tangle of abnormal blood vessels connecting arteries and veins in the brain.

It is likely she was born with the condition and there was nothing her family could have done to detect or prevent her death.

"She was healthy, she exercised, she didn't drink," said Kathryn, shaking her head.

"The specialist said it was like a ticking time bomb," Jacob added.

The family said the decision to donate Gabby's organs was easy; they knew it was what she wanted as she specified it on her licence, and she was a generous young woman.

"She had such a bright future in front of her and I would have just loved to see her future unfold," Kathryn said.

"We said goodbye to her and we knew that she was then going off to theatre - that she was the one giving the gifts on her birthday.

"She's given life to more than six people on her birthday, that is her legacy."

Jacob was brimming with pride over his sister's final gift.

"It's like she is living on in other people," he said.

The Marsh family urged people to openly discuss organ donation with loved ones and make their wishes known.

They hoped to one day meet some of the people that Gabby's organs helped.