KEY POINTS:
The four-month-old baby admitted to Starship Hospital with serious head injuries a week ago is believed to have suffered permanent brain damage.
Police are investigating the boy's 18-year-old mother, 19-year-old father and maternal grandmother over the "non-accidental" head injuries.
Both parents are unemployed, live in a state house and receive welfare benefits.
An ambulance was called to the parents' Papakura home last Saturday and the baby was rushed to Middlemore Hospital before being transferred to Starship.
The child was moved out of intensive care on Thursday and put into the hospital's high-dependency unit where it is expected he will remain for some time. It is understood the boy suffered major swelling on the brain.
The boy's 18-month-old brother has been taken into Child, Youth and Family custody and placed into the care of a relative.
CYF confirmed to the Herald on Sunday that, until last week, it had not dealt with the family.
