Singers voice betrays him after first song. What would you do?

[Norris]

My guitarist/main vox brings a carton of pineapple juice when his voice is a bit dodgy. I don't know if it really helps, but he keeps sipping it all night and has always got through the gig.

[sblueplanet]

When I played bass in a wedding band I used to take the main vocal for around ten tunes to give the singer a rest or a break off stage. Guitarist sang some too. Made sense when playing for several hours but not every band can be so versatile.