In high school she took courses at the National Youth Drama School, began writing music and performed principal roles in major school productions.
Jenna was born with an abnormal mass of tissue in her left lung, a rare condition called a cystic adenomatoid malformation, of unknown cause. She also has scoliosis, an abnormal curvature of the spine.
Immediately after her birth at National Women's Hospital, Jenna was placed in the neonatal intensive care unit because of breathing and heart problems. Within hours an operation was done at the Starship children's hospital to remove much of her left lung - the remainder has never functioned properly - after which she spent four months in the Starship ICU.
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She says after three weeks in Starship she suffered a near-fatal failure of her right lung when she inhaled milk because of a reflux problem. To deal with this, her stomach, in an operation at age 3 months, was hooked up to a liquid-feeding tube that emerges through her abdomen - a gastrostomy. She began eating some food with her mouth when she was 3, and although she now consumes a greater proportion of her food orally, Jenna still requires some tube-feeding to maintain her weight.
At age 4, Jenna moved from Christchurch with her family to Hawkes Bay. At 14, she had surgery at Starship to insert titanium rods into her back, which have largely corrected the scoliosis.
Jenna says the spinal problems did not greatly affect her growing up.
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"I can't do physical things like athletics. In high school I didn't let that stop me from giving it my all on school sports days. I suppose I'm lucky to have a passion for music."
Having only one fully functioning lung has not restricted Jenna's singing.
"I have to be realistic about breathing in between phrases in singing, but sometimes I do push myself.
"I have made all my singing teachers aware of this, we've always worked through it and I have always managed to produce a satisfactory performance which leaves the audience stunned."
Jenna faces more treatment. She needs chest reconstruction after ribs on her left side caved in. But for now she continues her studies and is preparing for end-of-year recitals.
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