How much would you gift for a Baptism?

-Its a family member's child
-Parents are holding a brunch after church at a nice restaurant
-Myself, DH and LOs are going

How much $$ would you put in the card? I was thinking $75??

I also wanted to add that it is out of state (not far though) but we will be getting a hotel room so that kind of factors into the cost of everything.