Urraca of Castille, daughter of Alfonso VI and mother of Alfonso VII.
Her half-sister Teresa, although she often signed as Regina, was not a proper queen, but she was the mother of Portugal's first king Afonso Henriques.
Jeanne d'Albret, aka Juana III of Navarre, daughter of Enrique II of Navarre and mother of Henri IV king of France.
Who were the queens regnant of history who were both daughters and mothers of kings? Several examples coming to my mind, off the top of my head, are Juana la Loca of Castile, Isabel II of Spain, Maria I and Maria II of Portugal, and Mary of Scots.
I'm not sure if Archduchess Maria Theresia of Austria would count, since she was technically only the consort of Holy Roman Emperor Francis -- his position being elected, no less.. That being said, she was the queen of Hungary and Bohemia, so she might qualify.
No queen regnant of England has been able to qualify, since Victoria was never a king's daughter, while Elizabeth II is still alive and kicking -- and might even outlive the Prince of Wales. Likewise, it's anybody's guess as to whether Queen Margrethe II of Denmark or Crown Prince Frederik dies first.
The Netherlands doesn't really count, since Wilhelmina (a king's daughter) became the mother of a queen regnant, not king; and Beatrix, although the mother of a king, was the daughter of a queen regnant, not king. Similarly, Isabel I of Castile doesn't count either, since she was the daughter of a king but the mother of a queen regnant.
Can anybody name additional examples? What about medieval history, which witnessed the reigns of several queens in pre-Spain (e.g. Castile, Aragon, Navarre)? Had Holy Roman Empress Matilda been successful in obtaining the English throne for herself, not just her descendants, she would count, since her father was King Henry I and her son became King Henry II.