Is it valid to give rent to a non-heir relative?

Is it valid to give property rent to a stranger or someone related, and deny it to a legal heir in the absence of any will? My brother is not giving me half of the rent but is giving it to my aunt, saying that this was our father's wish. It seems he is benefiting from it. What should be my argument in a partition suit to recover that money? How do I recover the 50% money being transferred to my aunt, who is not a legal heir while my brother and I are the legal heirs? How can I stop the rent being taken by my brother or aunt until the court decides the case? Does this argument hold in court if they say our father’s oral wish was to give 50% of the rent to our aunt (whom we haven’t met in the last 20 years)? He also claims that he has spent the rent money on property maintenance for the last 10 years since the case was filed in court. Is this maintainable in court?