My FH does not have much family, but what family he did have we invited because I believe family should always receive an invite. A frustrating part of this is they weren't a 100% sure on the address so we received some back as undeliverable. We even received one, this was a family friend however, back as undeliverable and written on the card was "<insert name here> has not lived here for 12 years". Very aggravating as I know the majority of family despite being large and if I did not have their correct address, I went by any means of getting it. Like one family member's invitation that came back undeliverable, I late found him on his mom's sister's/his aunt's facebook listed under the relatives. Did it never occur to his mother to verify with her sister that this was the correct address when she insisted on sending to all these people? As I said, aggravating and please forgive my little rant but the count is now up to 6 that we have received as undeliverable from that side and none from mine.
However, this post does have a point. We sent an invitation to his mom's cousins and they politely rsvp'ed no but just today (my mom, who the RSVPs were sent to) received a card saying despite never having met my FH (they are not a tight knit family and much of his family is spread across the US, although they don't even see family that lives in the same city as them) they thought it was very thoughtful that an invitation was sent and enclosed a check for $50. My question is, what is the etiquette on this? I read some posts on various websites while searching for this little scenario on google. Answers I have seen are - A. do not cash the check but send a thank you right away, B. do not cash the check but send a thank you right away and then once the check is cashed send another card with a photo saying their presence was missed, C. do not cash the check and send a thank you after the wedding which is when the check should be cashed, D. cash the check right away so they are not waiting for the check to be cashed so they do not get a "surprise" when it is cashed months later and send a thank you.