what can be legally done to this boy for raping my child

If you have knowledge that a crime has been committed and have not done so already, immediately pick up a telephone, dial 911 and report this crime to the police.

The crime must be reported to the police before any criminal legal action can take place.

Given that both parties are juvenile minor children, the legal outcome of any case that develops from reporting this crime would take place in a juvenile court setting. Any punishment or sentence imposed on the 16 year old would be determined by a family court judge based on the details of the case.

This crime would not fall under any adult criminal laws unless a court ruled that the 16 year old was to be charged as an adult.

I strongly advise you seek council from an attorney who specializes in juvenile law. An attorney can advise you if there are any other criminal or civil actions warranted against the 16 year olds parents.