Tonga's National Centre for Women and Children says parents need to be more careful in protecting their children.
Radio Tonga reports the Centre's Fuiva Kavaliku made the call following the sentencing of a man for sexually abusing a 9 year old girl.
The Supreme Court this week sentenced Sosefo Malu Kolo of Ma'ufanga to 12 years jail for the sexual abuse which occurred during 2010 and 2011.
The court was told the 65 year old often picked the girl up from school and took her to a remote area where the offence occurred.
He threatened to shoot her if she told her parents.
The abuse was eventually discovered when the teacher approached the girl about her absences from school.
Mrs Kavaliku says it's very important that parents and guardians take note of any change in the behaviour of their children.
And they should maintain closer links with their children's teachers.