Lyric discussion by trinity_tragedy 

A note on the origin of this song: "Lizzie Wan" (alternately "Lucy Wan") is an 18th-century English/Irish folk ballad, best known as The Ballad of Lizzie Wan, which recounts the tragedy of Lizzie Wan, who falls in love with her brother and then kills herself while carrying his child. Kate's original lyrics in the demo version of The Kick Inside included the line "Welling eyes from identifying with Lizzie Wan's story" making it clear that her own story refers to a modern pair of siblings who face a similar crisis. In the finished version as heard on the album, the explicit reference to the early folksong was removed, making the song's inspiration harder to identify. But her intent remains, as indicated by this excerpt from the original:

When will you return again,
My son, come tell to me?
When the sun and the moon set on yonders green hill,
And I'm sure that never can be.
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