It's Catholic confirmation season here.
DC have been told to address the Bishop as "Your Grace"
DD insists it's "My Grace"
But she's 10yo and charming and will probably offer him some cake at the same time so he won't notice.
Debretts tells me it should be; " Roman Catholic bishops are addressed in speech within their community as ‘My Lord’ or ‘Your Excellency’"
I'm going with "Your Grace".