Now the determined teenager has been fitted with a special weighted prosthetic arm to allow her to fulfill her dream of throwing a javelin in the London 2012 Paralympics.
Hollie, 17, has spent years perfecting her javelin technique, but was held back by having no right arm to provide crucial balance.
She has now been fitted with a specially weighted prosthetic arm by a company that provides limbs for injured soldiers, and is competing in the London Paralympics.
Hollie's mum Jill, 47, says: "We are all very proud of Hollie. She has never let only having one arm stand in her way. She has always been a very determined girl.
"She learnt to throw the javelin with her left arm, and has done very well. But since having the special prosthetic arm fitted, she has gone from strength to strength."
Doctors discovered that Hollie was missing a right arm below her elbow on a scan when her mum was 20 weeks pregnant.
Jill, a child support assistant, who lives with husband Graham, 48, a joiner, in Ystrad Manach, South Wales, says: "I got a phone call after the scan was carried out to say could I come back to the hospital as they thought my baby's arm was missing.
It was a massive shock. I was referred to another hospital for a high definition scan as the doctors were worried that something else would also be wrong with the baby.
"Luckily they discovered she was perfectly normal, apart from her missing arm, and they couldn't explain why it had happened."
Hollie was fitted with a cosmetic arm when she was three months old and she even learnt to crawl using it. But as she grew older she discarded the arm, preferring to live her life without it.
"She got on so much better without it - it really was remarkable," explains Jill.
At the age of five she could even tie her shoelaces with one hand, and she was always the first dressed after her school PE lesson. She just learnt to adapt and live without it.
Hollie became interested in javelin throwing after watching her older brother Ashley take up the sport when she was 10.
"We are a very sporty family and Hollie went to watch Ashley throwing the javelin and she decided that she wanted to do it too.
"Once Hollie has set her mind to do something, she usually succeeds, so we weren't surprised when she began to do so well."
Hollie had her javelin supplied by Caudwell Children's Charity in 2008 for the Beijing Paralympics where Hollie competed aged just 14 and became the youngest ever thrower competing in the games.
Then the charity stepped in again to provide her with a special prosthetic arm to help her improve her balance. The £5000 arm was made by Rehab Prosthetics, a company which makes prosthetic limbs for injured soldiers.
"She was always good at throwing the javelin but having no right arm meant that it was more difficult for her," says Jill.
"So she was given a prosthetic right arm that was specially weighted to be able to provide her with the right balance that she needed for throwing. Hollie was thrilled when she got the new arm as it has improved her throwing technique tremendously, and she wants to go far."
Hollie competed in New Zealand in January using the new arm and won a bronze medal in the World Senior Championships, which ranked her third in the senior world. She also competed in Dubai in the Junior World Championships and came away with a gold medal and a Javelin Record, ranking her first in the junior world.
She has now been selected for the 2012 London Paralympics and hopes to bring back another medal.
"Having the new prosthetic arm has really helped me tremendously.
I can throw a lot better now and I can't thank Caudwell children enough for their kind donation and continued support. I also have a new arm that I use for gym work, which has allowed me to build up my fitness much more too.
A year ago the family moved from their home in Grimsby to Wales to access coaching and other help to enable Hollie to pursue her career.
" Hollie has never let anything hold her back and we are so proud of her," says Jill.
"With this new arm, she can reach new heights, and we are excited about what the future holds for her."
What a fantastic story! Good luck this summer, Hollie!
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