Comhghairdeas!

I guessed the answer the first time "Liam's brother" published 2 verses of "A NEW BALLAD CALLED 'JOSEPHINE'S DOWNFALL'" but then I knew that Martin Ryan was marrying/ is married to a "Josephine". I still don't know whether Dan Milner has a brother named "Liam".

Are Martin and Josephine not hosting a singaround to celebrate? (I know singers who hosted birthday events on Zoom this year).