My FI is a twin, and his family has this crazy weird obsession of making things "equal" in regards to them (like they get the same Christmas gifts or the monetary equivalent).
FMIL told FI that they are paying for our DJ, photographer and the rehearsal dinner (because they did that for his twin when he got married 5 years ago)!
Yay! It's a done deal, as they ALWAYS follow through on promises (though we still have the money budgeted because we are paying for the wedding ourselves).