Meredyth was sent to Horn Hill at the age of eleven. There under her aunt, the competent and capable Lady Leonette of loyal House Tarly, she learned the ways if being a highborn lady. She was lonely at first, being away from her beloved Highgarden and her family, but Lord Baelor had too many children to keep locked away in his castle when they could be strengthening alliances with his vassals. He thought to one day marry her to the future Lord Tarly.
Meredyth thrived at Horn Hill. The holdfast had no lord for over half a decade, and so the Lady Tarly ran the affairs of the castle and taught Meredyth more than she ever would have learned at the Reach's capital.
Maude was the oldest daughter and the most beautiful, and Mellara was the youngest and known for poking her nose into places it didn't belong. Meredyth was the middle child, and the awkward position suited her awkward personality. Where Maude was beautiful, Meredyth was decidedly plain. Maude had long legs; Meredyth had a long nose. Maude was lithe; Meredyth was gangly. Maude smiled and giggled at the men in court; Meredyth stood sullen and silent. Her brown hair was duller than her sister’s, and her golden eyes didn’t hold quite the same sparkle.
Any plans for a marriage between Lord Bonifer Tarly and Meredyth Tyrell were laid to waste when war broke out. Being at Horn Hill kept Meredyth safe from harm, but when the battles ended and the dust settled, it was back to Highgarden she found herself being shipped, to marry Lord Robert Manderly at the age of seventeen in order to secure his claim to the castle he stole from her father.
Meredyth returned to Highgarden to marry Robert Manderly in place of her sister Maude Tyrell. She and her brother, Maester Olyvar Tyrell, at the urging of and with assistance from Queen Danae Targaryen, conspired to poison Robert and were successful. After a long, agonizing sickness, he died, and Meredyth became a widow.
The ironborn, led by Dagon Greyjoy, seized Highgarden during the War of the False King in order to secure the Rose and Ocean roads for passage of the the Westerlands' armies. They occupied the castle for the duration of the war.
In the fourth era, Meredyth and Olyvar witnessed a white raven arriving in Highgarden, signaling the arrival of summer.
After the war's conclusion, King Damon Lannister and Queen Danae Targaryen stayed in Highgarden on their way back to King's Landing, where they informed Meredyth of the death of her sister, Mellara. Danae was given a gift of poisoned wine at their arrival feast and fell ill, nearly dying but for the intervention of Olyvar. After Olyvar was granted his lordship for saving the life of the Queen, Meredyth traveled to King's Landing to become a handmaiden for Queen Danae Targaryen.
After hearing of Ashara Lannister's ball in Oldtown, Meredyth returns to the Reach for the first time since moving to King's Landing. While traveling south, she and her party stop at her former home of Highgarden, to visit with her goodsister, Melessa Tyrell, before continuing the rest of the way. She and her brother, Olyvar Tyrell, reunited in Oldtown and she met her niece for the first time.
Baelor Tyrell , father (deceased)
Olyvar Tyrell , brother
Troy Tyrell , brother (deceased)
Maude Tyrell , brother (deceased)
Benjen Tyrell , brother (deceased)
Mellara Tyrell , sister (deceased)
Elyana Tyrell, niece