They later revealed one of her arms had to be amputated.
A GoFundMe campaign initiated by the family has raised A$424,129 (about $515,000).
Her brother Josh Stewart posted an update to the page today revealing a grim prognosis for the “passionate teacher” and “loving mum”.
“Given the extensive open wounds contaminated with sand and debris, the risk of infection is extreme,” he said.
“Please pray for her during her continued surgery and for her body to heal without infection.”
Leah Stewart suffered severe and life-threatening injuries with multiple bites across her arms and legs.
Josh said family had planned to pin up photos of happy memories around Stewart’s room “for when she becomes conscious”, and thanked friends who visited his sister with a playlist of her favourite songs.
“We’ve been blown away by the support, care, love and generosity we’ve received for Leah,” he said.
“Your love, concern and help has made a world of difference to giving Leah and her little family some stability and hope for her recovery.”
Stewart’s mother Christine, who is a registered nurse, and her partner Fernando have remained at her side while she receives treatment in intensive care.
Fernando was presenting at an overseas work conference when the attack happened.
Stewart was reportedly swimming laps close to the shore and between the flags when the shark struck.
Verco told the ABC he saw the shark drag Stewart underwater and the water quickly turned “very bloody”.
“She was lucid enough to say, ‘Help’, and respond to instruction, but she was very much in shock,” Verco said.
Verco said he reassured Stewart as he paddled her to shore, telling her she was doing well and that help was close.
Flight path restrictions meant shark surveillance drones were not operating over Coogee Beach when the attack happened.
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