what is the role played by this character?
Daenerys is one of the last surviving members (along with her older brother, Viserys) of House Targaryen, who, until fourteen years before the events of the first novel, had ruled Westeros from the Iron Throne for nearly three hundred years prior to being ousted.
Daenerys Targaryen
 Daenerys is one of the last surviving members (along with her older brother, Viserys) of House Targaryen, who, until fourteen years before the events of the first novel, had ruled Westeros from the Iron Throne for nearly three hundred years prior to being ousted. 
what is the name of the mother of dragons Daenerys Targaryen who is the aforementioned? She  is a fictional character in George R. R. Martin's "A Song of Ice and Fire" series of novels, as well as the television adaptation, "Game of Thrones"
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Daenerys Targaryen [SEP] Introduction
Her brother loses the ability to control her as Daenerys finds herself adapting to life with the "khalasar." Her character emerges as strong, confident and courageous. She becomes the heir of the Targaryen dynasty after her brother's murder and plans to reclaim the Iron Throne herself, seeing it as her birthright. A pregnant Daenerys loses her husband and child, but soon helps to hatch three dragons from their eggs. The dragons regard her as their mother, providing her with a tactical advantage and prestige. Over time, she struggles to maintain control of her dragons. She also acquires an army with which she conquers the cities of Yunkai, Astapor and Meereen, determined to end slavery and injustice there.