Good grief. Seems to me that a church is God's house and I'm pretty sure He loves breastfeeding (that's why He gave us boobs after all).

Furthermore, being old doesn't give people an excuse to be ignorant. If one her old relatives didn't like mixed race relationships and your partner was a different race to you, would she ask you not to bring him? Or if another member of th family was gay and someone didn't like that, would they be excluded?

Me, I'd go and feed my child when he required it. I would also seek out the photographer and make sure s/he got a shot of me feeding. That would be my special EFF YOU to the bride in answer to her DO NOT caps.