bill spedding , the person of interest in the william tyrrell case , has been charged with five counts of child sex abuse .
he was living with three boys at the time william vanished - despite authorities being aware of the claims against him .
the nsw ombudsman confirmed they are ` making inquiries ' into how the boys came to be living with spedding .
` someone needs to be held accountable , ' the boys ' mother said .
victoria police are investigating his alleged involvement in a paedophile ring and expect to lay more charges .
spedding has denied any involvement in william 's disappearance .
he was refused bail on thursday after a brief court appearance .