If she doesn't get neck stabilisation surgery or similar, her condition will continue to deteriorate, eventually confining her to a wheelchair fulltime.
"I've been told I could have paralysis in my spine and neck, which wouldn't be a very enjoyable way to live," Gendi said.
"EDS is random; I have good days when everything is pretty normal and bad days when I'm sore and tired and can't do much.
"It's got worse as I've got older ... Will is heading down the same path."
The medical laboratory student was diagnosed with EDS when she was 8, after years of joint dislocations, bruising and severe pain.
No one in her family had previously been diagnosed with EDS.
She hasn't let the disorder limit her. The keen sportswoman swam competitively for 10 years and, intrigued by health science, she moved from Christchurch to Dunedin for university. Will also swims and hopes to study engineering after school.
"If I allowed EDS to have too much of an impact, I'd never get out of bed," Gendi said.
Neck stabilisation surgery would likely cost hundreds of thousands of dollars, which would be a struggle for the family, who have had to spend tens of thousands repairing their earthquake-damaged home.
"I don't like asking for money, but we couldn't go to America without it, and money raised will also go towards helping my brother," she said. Gendi and her mother will fly to America in December or January.
To support the Roberts siblings, go to givealittle.co.nz/cause/genditousadoctors
