A 22-year-old woman and her 20-year-old brother have been charged with serious assault offences after a 14-year-old boy presented to hospital last week with significant injuries.

Police say the boy was taken to the Canberra Hospital on Tuesday, suffering multiple injuries consistent with an assault.

By Thursday his condition was critical and he was airlifted to specialist children’s care in Sydney, where he remains in a critical but stable condition.

Police believe the boy was assaulted at a Belconnen home early on June 23.

Police searched the home on Saturday, where the sister and brother were charged with recklessly inflicting grievous bodily harm and assault occasioning actual bodily harm.