The investigating officer will not arrest the accused (your family members) in connection with the offence of cruelty. In this situation the investigating officer shall issue a notice under Section 41-A of the code of criminal procedure.
You should comply with that notice and cooperate in the investigation. If the allegation made in the FIR is false then you should move a writ petition before the High Court for quashing of FIR.
In Bhajan Lal case the Supreme Court has held that if the allegation in the FIR holds no field or prima facie no offence is made out against the accused the court has power to quash that frivolous FIR.