A 16-year-old boy has been charged with six counts of rape of his 9-year-old nephew while a 14-year-old boy was charged with two counts of rape of his 12-year-old sister.
There were 10 victims last month of whom six victims were under the age of 18 years.
There were eight female victims and two male victims.
There were seven incidents where the victims and the accused were related to one another.
While confirming the statistics for serious sex offences for the month of May, the Office of the Director of Public Prosecutions says there were 10 indictments filed in the High Court with a total of 30 counts of sexual offences.
There were 17 counts of rape, 2 counts of indecent assault, 2 cases of defilement and 9 cases of sexual assault.
Of the 10 accused persons, two were juveniles.
A 30-year-old man was charged with the rape of his 12-year-old niece while in another incident, a 25-year-old man was charged with the rape of his 15-year-old cousin.
There was one incident where a 52-year-old man was charged with two counts of indecent assault, eight counts of sexual assault and two counts of rape of his 18-year-old niece.
A 40-year-old man was charged with one count of sexual assault and three counts of acts with intent to cause grievous harm to his 40-year-old wife.
In another incident, a 27-year-old man was charged with the rape of his 36-year-old defacto partner.
A 66-year-old man has been charged with the rape of a 15-year-old boy while in another incident, a 20-year-old man was charged with the rape of a 28-year-old woman.
A 37-year-old man was also charged with two counts of defilement of a 15-year-old girl.
