This is what's set on the phone. To change it, open Family setup on the phone — this list updates the next time the phone is online.
Do this once, together, while everyone's here — birthdays, the anniversary, and a few just because. Carol passes each one on, once, on the day you choose. Ten minutes now beats trying to remember in March.
Carol reads messages out loud and can't take a reply, so she won't say phone numbers, amounts, links or logins. Keep it to the kind of thing you'd say across the kitchen table.
Type this into Carol on their phone, once, while you're there.