Hoo-ee!

My bridal party table had, from left to right as the guests would see it:

Chief Bridesmaid, Best Man, Mum, Dad, Me, DH, MiL, FiL, Bridesmaid, Usher. I know my sister (the Chiefy) should have sat next to FiL and my cousin (normal bridesmaid) at the end, but both Sis and FiL could well rub each other up the wrong way and cause an argument.

Boyfriends. I disliked inviting "and guest" for friends if I didn't know the boyf, but a bridesmaid's boyf should be invited really. My mum insisted on the "and guest" bit, which narked me off as I wanted more of the people I knew to the meal and fewer of those I didn't. If it was a long-standing boyf, fiancé or hubby then of course they were invited, no matter how well I knew them.

Children. I have had to refuse a no-children invite for a friend. DS will be four months old, it's a 10-hour do with no children and tbh it's 300km away - I'd have to drive that on the Thursday night, DH would need the Friday off work to attend, DS would be cranky because 10 hours without me is too much, I aren't willing to express feeds for not only the car journeys but for the wedding day too... it's a very dear friend, but I just can't do it. If DS was able to attend we may consider it, but 300km is a jolly long way. If DS cried at all I'd take him out of the service/room because it's her big day, but I respect she wants no babies and she respects that I can't make it. I do think a baby niece is different to an older child who would need a meal, would your sister be OK with sitting near the door so she could escape should Lucy cry? It sounds like your relationship with your sister is already a bit rocky and not inviting Lucy could tip her over the edge again. Older children can be babysat, 4 month old babies can too but personally I'd not trust my mum or MiL with DS at this age for a long period of time.

You can tell your sister that the alcohol in the evening may make it unsuitable for a baby, but it's her choice... I know that my sister would blow a fuse if I didn't invite her and her baby (should she have had a baby) and it's just not worth the family rift from a wedding. You'll be so wrapped up in you and your new Hubby to even notice a baby (we attended a wedding when DS was 6 weeks old and the couple never even noticed him getting cranky, but they told me they really wanted the babies there).