Elrond and Alex McCarthy, parents of Kaia and 4-year-old Amelie. Photo / SuppliedElrond and Alex McCarthy, parents of Kaia and 4-year-old Amelie. Photo / Supplied

A glowstick accident led to Kaia's rare eye cancer diagnosis. Photo / SuppliedA glowstick accident led to Kaia’s rare eye cancer diagnosis. Photo / Supplied

Kaia McCarthy with her sister Amelie. Photo / SuppliedKaia McCarthy with her sister Amelie. Photo / Supplied