Prince Robert is Child ballad number 87, existing in several variants, and a murder ballad

Murder ballad

Murder ballads are a sub-genre of the traditional ballad form, the lyrics of which form a narrative describing the events of a murder, often including the lead-up and/or aftermath...

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Synopsis

Prince (or Earl or Lord) Robert married against his mother's wishes and went to beg her blessing. She prepared a wine cup with poison, put it to her lips without drinking, and gave it to her son. He died. The bride was summoned on the pretext of a meal and told the news, and that she will get nothing of his property. She wants none of his property but the ring on his finger that was promised to her, but even that is denied her. She dies, and they are buried together.

Motifs

Francis James Child

Francis James Child

Francis James Child was an American scholar, educator, and folklorist, best known today for his collection of folk songs known as the Child Ballads. Child was Boylston professor of rhetoric and oratory at Harvard University, where he produced influential editions of English poetry...

 noted that other ballads included a mother who poisoned her son over a match, but considered none to compare to this one.

Willie's Lady

Willie's Lady

Willie's Lady is Child ballad number 6.A variant of this ballad was one of 25 traditional works included in Ballads Weird and Wonderful and illustrated by Vernon Hill.-Synopsis:...

also revolves about the mother's hostility.

The poisoner who feigns drinking her own poison is also found in the Scottish fairy tale Gold-Tree and Silver-Tree

Gold-Tree and Silver-Tree

Gold-Tree and Silver-Tree is a Scottish fairy tale collected by Joseph Jacobs in his Celtic Fairy Tales. It is Aarne-Thompson type 709, Snow White. Others of this type include Bella Venezia, Nourie Hadig, and Myrsina.-Synopsis:...

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