The couple we have in mind isn't married through church. We had them in mind for Maid of Honor and Best Man because we have a close relationship. They have a great married relationship and are somewhat of an example in our eyes. He is my FI older brother so, because they are not catholic, could they participate still or should we ask our priest? We haven't asked them for the honor of being, because we want to make sure.
Thanks for your input guys, it is greatly appreciated.