We had this issue after flying to NZ in Uagust for my BILs wedding....it was a PITA

We ended up getting a hotel room (it was at a hotel) and we and the family took turns babysitting the 2 girls upstairs in shifts after teh reception.
Worked out well, but it was a pain and quite frankly, had we known the children werent welcome before we spent $4000 flying to another freaking country I and Charlotte would not have gone in the first place... *grumble*

Anyway, I would speak with the bride directly and work out where to go form there.
If bubs isnt welcome, then perhaps both of you stay home