A: The short answers: No, it's not redundant, and yes, you should send them. While you're right that clearly they know the scoop on the wedding, they're still going to want an invite to remember the day. So while they don't necessarily need an invite, it's still a lovely gesture to send one.
Who gets their own wedding invitation?
It's one per household, not one per individual guest that is invited. Any child age 18 years or older should receive their own invitation regardless of whether they still live at home with their parents. Roommates get their own invitations.
What percentage of wedding invites actually attend?
“A general overall percentage between 75-85 percent of wedding guests usually attend.” The breakdown: 85 percent of local guests, 55 percent of out-of-town guests, and 35 percent of destination wedding guests will show up, Buckley said.