My FI is the fifth, youngest, and only guy of his family. His sisters (all married, with children) range from 33 to 43. His oldest sister once told him that she'd feel ridiculous as a bridesmaid, so I don't want to give her the option and have her feel pressured to say yes if she really doesn't want to do it. On the other hand, I would feel like I'm the "bad guy" to their family if I don't ask her and ask the other three. The other three sisters I know would love to be in the bridal party. Is it rude to ask his oldest sister and her husband to do the readings while the others are in the wedding party?
FYI- We are both very close with our families. I already have 2 sisters (my 2 MOHs) and a best friend in the party.