it fits to Hetalia characters so well... lyrics are about sisters not brothers but it's lovely anyway:
Three sisters stand by the coast of sea
Their are pressed by weakness and tiredness.
There waded land and spirits
Of honour and sense of three nations.

But in the towers of destiny belling loud
And the sea starts to wave.
Three sisters wake up from the sleep,
Come to stand for theirselves.

The Baltics is waking up, the Baltics is waking up
Lithuania, Latvia, Estonia!