Source: {ref:S905@Cawley} says her parents married about 1050 to 1054 based on the assumed birth range of their eldest son.

Source: {ref:S756@Weis} says her parents married about 1080 and {ref:S925@Cawley} says their daughter Alice was born between 1090 and 1095, presumably later than earlier.

Source: Cokayne says he was 21 in a document dated after 1226

Source: {ref:S756@Weis} says her mother was born about 1267, probably because her parents married in 1266, so the earliest Margaret could have been born was about 1282.