The lyrics are from the Solomon Islands (small islands north of Australia).

(Baegu)
Sasi sasi ae ko taro taro amu
Ko agi agi boroi tika oli oe lau
Tika gwao oe lau koro inomaena
I dai tabesau I tebetai nau mouri
Tabe ta wane initoa te ai rofia

Sasi sasi ae kwa dao mata ole
Rowelae e lea kwa dao mata [bad word] I dai tabesau I tebetai nau mouri

Sasi sasi ae ko taro taro amu
Ko agi agi boroi tika oli oe lau
Tika gwao oe lau koro inomaena
I dai tabesau I tebetai nau mouri
(repeat x 3)

English version:

Little brother, little brother, stop crying, stop crying
Though you are crying and crying, who else will carry you
Who else will groom you, both of us are now orphans
From the island of the dead, their spirit will continue to look after us
Just like royalty, taken care of with all the wisdom of such a place

Little brother, little brother even in the gardens
This lullaby continues to the different divisions of the garden,
From the island of the dead, their spirit will continue to look after us

Little brother, little brother, stop crying, stop crying
Though you are crying and crying, who else will carry you
Who else will groom you, both of us are now orphans
From the island of the dead, their spirit will continue to look after us
Interpreting the Song:

The Baegu lullaby heard in Sweet Lullaby is from Northern Malaita (Solomon Islands) recorded by ethnomusicologist Hugo Zemp. The song is called Rorogwela and is sung by Afunakwa.

The lullaby is about a young child crying because his parents are not around. In response his older brother sings this song [bad word]  as well as tell him the reality, with an appeal for his deceased parents to protect this child in the land of the living (local ancient belief is that the dead care for loved ones they left behind).