Conan O’Brien showed off his sweet singing voice for guest Josh Groban on Monday night with his rendition of the classic Irish lullaby ‘Tura lura.’

The Irish American comedian is preparing for his vocal debut during a live Simpson’s event at this year’s Hollywood Bowl, where America’s favorite Simpson’s clips will be played on a big screen, along with an orchestral accompaniment.

Conan will be performing his ‘Monorail Song,’ and he asked singer Groban for some pointers.

“If I’m going to analyze what you’ve got, I kind of need to hear a little bit of what I’m working with,” Groban told him.

“How about an Irish lullaby?” Conan suggested, before beginning, “as a young boy in Killarney, so many years ago…”

After Conan finished the tune in his high pitch, Groban’s only suggestion was to sing it a bit lower, and then gave us his own quick rendition.

Tell us what you think of their versions of Tura lura – does it remind you at all of childhood?