Going to try and keep this short...
One of FI's groomsmen's wife is due to have their first child right around our wedding date. While I COMPLETELY understand if that takes precedent over our wedding (it should), the groomsmen noted to FI that "he should have a back-up ready, just in case."
If he has doubts about whether or not he can make it due to his child's birth, is it rude to offer to replace him ahead of time, or should I just expect to roll with the punches and if we need to replace him the day of the wedding we will?
Note: Our ushers are wearing the same tux as the groomsmen, so it wouldn't be a complete inconvenience to have a stand-in.