What does “fill yer can” mean? Line from an Old Blind Dogs song….

In the song “Lay Ye Doon Love” the Old Blind Dogs sing:

I’ll lay ye doon, love, I’ll treat ye decent
I’ll lay ye doon, love, I’ll fill yer can
I’ll lay ye doon, love, I’ll treat ye decent
For surely I’m an honest man
———

What does “I’ll fill yer can” mean?

Thanks from a clueless yank!



by jonandgrey