Listing grandparents in the wedding program

I am wondering what the correct etiquette is for listing grandparents of the bride and groom in the wedding program if they are unable to attend. His parents are divorced and only the grandparents of his mom and his step-dad are able to attend the wedding. Do we only list their names or do we list all our grandparent’s names with “unable to attend” next to all of those who cannot attend. Or, do we just leave the grandparents out all together? Thanks so much!

Weddings by Shayna

The ceremony program is most useful for guests to understand who is attending and participating in the wedding. It would be logical (and in this case, probably helpful) to just include those who will be seated specially during the ceremony.

Or, you could include a couple of lines somewhere else in the program saying that the bride and groom are grateful for the support of those who could not attend, including (list grandparents). That would acknowledge their importance, but not confuse people about the actual flow of events.