Mellara Tyrell was a short, skinny, unathletic girl from Highgarden. Throughout her childhood she was known for sticking her nose into other's business, and she tended to eavesdrop despite her father's scoldings.
Mellara was captured by Thaddius Lannister , along with her brothers Benjen Tyrell and Troy Tyrell outside of Oldtown. While being escorted to the capital, she watched as Benjen killed Troy after they were forced to fight to the death. She was a prisoner at the Red Keep for the duration of the Ascent of the Lion.
After the war's conclusion, Robert Manderly was given Highgarden. He was to marry Maude Tyrell to solidify his claim, but the oldest Tyrell daughter committed suicide. Meredyth Tyrell was wed to him in her sister's place and Mellara was taken back to Highgarden as a ward.
It was discovered at the end of the fourth era that Mellara was imprisoned and tortured at Highgarden for close to two years. She became only a shell of her former self.
Mellara was disemboweled, burned alive, and hung from the massive tower in Old Town, the act being a ruse meant to goad King Damon Lannister into believing that his sister Ashara Lannister had been killed.
A newly-built motherhouse in King's Landing was named in Mellara's memory.
Baelor Tyrell, father (deceased)
Olyvar Tyrell, brother
Maude Tyrell, sister (deceased)
Meredyth Tyrell, sister
Troy Tyrell, brother (deceased)
Benjen Tyrell, brother (deceased)