At my last church there was (and still is) an elderly man who has learning difficulties (he shouts out and repeats what others are saying). When the current wonderful priest moved there, he asked him to be an altar server at the early morning Sunday Mass, where there are no other servers.
The man always carries out all the tasks without making mistakes, and when he adds his own comments or repeats some of the priest’s responses, the priest just says “That’s right, (name)” and smiles at him.
This priest is a holy and spiritual man, how he’s dealt with this parishioner is fantastic. He never thought to quieten him or exclude him, he drew him right into the Mass.