Petra Tallhart

Lady Petra Tallhart is an unseen character in Game of Thrones. She is not expected to appear in the series, being long dead by the time it starts.

Background
Petra married Lord Tyrek Tallhart, with whom she had the daughter Hollys.

Season 1
She is mentioned in The Lineages and Histories of the Great Houses of the Seven Kingdoms.

Reference

 * "A Golden Crown"