Possible Clues:

• Singer from Switzerland in Brazil raising young lad
• A treble in church
• Do-gooder on Sundays?
• Working in service he does treble duty
• Singer heard in The Abbey and in The Family
• Chorus gets one of the juniors to sing the praises of the man upstairs
• Singer in a loft
• Singer in Switzerland and in Brazil set up by young male
• Singer shy about admiration for rugby body