I see it mentions some singing of the psalms, but, is this the same St. Gregory, Doctor of the Church that gave us Gregorian Chant? I don’t see that mentioned specifically? If it is, this is my youngest sons confirmation namesake. I just don’t know if there are 2 Gregorys as Doctors of the Church?
You're thinking of Pope Gregory, he's the one associated with Gregorian Chant:
Pope St. Gregory I ("the Great")
Doctor of the Church; born at Rome about 540; died 12 March 604. Gregory