From A Wiki of Ice and Fire
Cersei, Melara, and Maggy. Artwork by Cris Urdiales, used with permission.
|Born||In 264AC or 265AC|
|Died||In 276AC or 277AC|
|Book(s)|| A Feast for Crows (mentioned)|
A Dance with Dragons (Mentioned)
Appearance and Character
Cersei describes Melara as a girl older than Jeyne Farman. She is contrasted to the "fat" Jeyne, implying she was slender or outright skinny. Melara was pretty, though she had freckles. The girl was "healthy as a little horse".  Cersei has troubles recalling what Melara looked like, as the memories faded as the years went by.  Cersei thinks of her as bold, certainly bolder than Jeyne and possibly bolder than Cersei herself. 
Melara, then eleven years old, visited Maggy with Cersei Lannister and Jeyne Farman during the tourney for King Aerys II after hearing whispers that she could tell futures. Jeyne fled when Maggy opened her eyes to greet the visitors, but Melara and Cersei stayed and insisted on hearing the future. Melara was present when Maggy made the prophecy of the valonqar to Cersei Lannister. Melara asked if she would one day marry Jaime, but Maggy told her that she would die that night, and her death was close. Many years later, Cersei told Taena of Myr that Maggy's prophecy had come true: Melara drowned in a well. It is implied that Cersei herself killed Melara by pushing her into the well and leaving her to drown.