Spinoff to RD Etiquette

What is the RD (rehearsal dinner) etiquette on who pays for it?
Grooms side? Brides? or Both?

I ask since I have a feeling its going to be a prob down the road for me. FH has a older brother who is married, NO RD took place therefore, his parents didnt pay nor did they pay for anything.
His sister got married, Her FH/DH parents paid for the RD. FH parents paid for a decent portion of her wedding.

Now for our upcoming wedding, I am kind of expecting them to take care of RD. As for wedding, FH and I are paying for it all by ourselves.
We had an e-party and my parents paid for it ( I hear also tradition, proper).


So, am I wrong for expecting that?

TIA!

Traditionally it's the groom's family. But in this world nowadays, anything goes!!! Def talk it out with them and see if they'll do it, or at least help you guys out. Esp since you're paying for the whole wedding yourselves. Good luck!!

I would help you..but I have no clue...

I think it's normally the groom's family, but in my case, FH and I are paying for it.