Hi
Depending on the charge sheet and witnesses case will be decided after trial. However your father-in-law the real victim is caught up in the counter case filed by his nephew.
technically you have an option to move a petition in the high court, for quashing the FIR lodged against him by his nephew, on the base of the incidents and facts as can be considered as under:-.
Your father in law was attacked
He had file FIR FIR first and also had loss of things.
He is a senior citizen and Uncle of MR.A.
In retaliation the second FIR was lodged by nephew.
you also see what is the status of the case , if both parties come together an settle it and the I.O can file areport accordingly and end it. From your query the status of the case is not clear
Since the sections in both FIR are non compoundable even if the settlement takes place , the case cannot be withdrawn. However the witnesses can be mad hostile in the trial, if the parties decide to settle the matter.
If FIR has filed against the father in law, let him apply for anticipatory bail .If in case the bail has been granted, he should move ahead with the quash petition.
The quash petition can-be also filed dafter the charge sheet filed by the police.