question: Who is the paternal grandmother of Eric I Of Denmark?
context: Title: Sweyn II of Denmark
  Passage: Sweyn II Estridsson  (– 28 April 1076) was King of Denmark from 1047 until his death in 1076. He was the son of Ulf Thorgilsson and Estrid Svendsdatter, and the grandson of King Sweyn I Forkbeard through his mother's line. He was married three times, and fathered 20 children or more out of wedlock, including the five future kings Harald III Hen, Canute IV the Saint, Oluf I Hunger, Eric I Evergood, and Niels. He was courageous in battle, but did not have much success as a military commander. His skeleton reveals that he was a tall, powerfully built man who walked with a limp.
  Title: Eric I of Denmark
  Passage: Eric I (– 10 July 1103), also known as Eric the Good , was King of Denmark following his brother Olaf I Hunger in 1095. He was a son of Sweyn II. His mother's identity is unknown. He married Boedil Thurgotsdatter.
answer: Estrid Svendsdatter
citations: Sweyn II of Denmark Eric I of Denmark