The folk tale of Oluronbi

Here's a story about Oluronbi, a young woman who makes a foolish promise. I remember the song pretty well but I'm a bit hazy about the story or where the song features in the story. I decided to go ahead and post it since everyone I ask about the story bursts out in the song but are less able to recall all of the story.

Based on the apparent popularity of the song and the number of people who claim to have seen theater or tv productions of Oluronbi (self not included), hopefully someone will help me out here or point me to book about Oluronbi so I can refine the story.

Edit:
Okay, a google search would have been useful. I did this a while ago but believe I searched for 'Olurombi'. A search for Oluronbi now yields this link to a 1929 book of Yoruba Legends by M.I. Ogunmefu where Oluronbi was turned into a bird by the Iroko tree which sang the song. She was later saved by her husband, a woodcarver who tricked the Iroko tree into accepting a wooden child in place of Oluronbi's child.
There's another link to a movie based on the Oluronbi story, but a different spin is given here - Oluronbi went to the Iroko tree to sacrifice her child in exchange for riches.

A wicked half-sister story

A new story is long overdue so here is the story of two half-sisters and an old man.

This story is based on the “wicked half-sister” theme ever so popular in folktales and fairy tales the world over. The result of this popularity is that elements from other sources/stories got jumbled into my recollection, however I believe those have been sifted out now (with some effort). It reminds me of Cinderella but of course, there are certain marked differences e.g. like the stepmother already existed before the demise of the good mother (hence half-sisters rather than step-sisters) and there are no charming princes.

But just like Cinderella, the good sister bore her burden silently and did as she was told. In the various versions of this story, she is always nice and docile to an extreme and I silently wondered about these as a kid, wondering if one had to be extremely docile (sometimes bordering on stupidity) to be good. So when I read Hans Anderson story of Big Claus and Little Claus, I really liked it. The theme of that story is similar – poor little guy and rich big bully. But when little Claus came across his riches and big Claus shook the story out of little Claus, little Claus sent big Claus on a fools errand which ended up with him being beaten up. Of course he came back looking for little Claus but little Claus had more surprises for him.