Margaret was a younger sister of Henry Courtenay, 1st Marquess of Exeter.
Their maternal first cousins included among others, Arthur, Prince of Wales, Margaret Tudor, Queen consort of Scotland, King Henry VIII of England, and Mary Tudor, Queen consort of France.
When she was young she was partly raised under the protection of her aunt Elizabeth of York and lived in 1502 at the Queen's residence at Havering Palace.
However, there is information of her living in Richmond on 2 July 1520, when she is mentioned attending to her young first cousin, once removed, Princess Mary Tudor.
When he became Earl of Worcester in 1526, his countess was his second wife Elizabeth Browne, allegedly an ex-mistress of Henry VIII's.