It is alleged the woman was attacked on Tuesday night at the Waterford Plaza shopping centre in Karawara when she went into cardiac arrest following the attack.
She was taken to the intensive care unit at Royal Perth Hospital where she remained until passing in the early hours of this morning.
On Wednesday, the family spoke to the ABC where they said she was unlikely to survive her injuries, her brain “swollen too much”.
The alleged teenage boy behind the incident briefly attended Perth Children’s Court on Wednesday and was charged with grievous bodily harm.
He was remanded in custody.
*The woman has not been named for cultural reasons.
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