Around 1604, or Christmas 1606, Lord Tyrconnell's only son,
Hugh Albert, was three weeks shy of his first birthday when the Earls sailed from Lough Swilly, and was raised in Louvain, Spanish Flanders. In time he joined the service of the
King of Spain, and was killed in action when his ship engaged a French vessel in August or September 1642 and caught fire. He succeeded his father as 2nd Earl of Tyrconnell, but left no offspring; the title of Earl would have descended to his first cousin
Domhnall Oge's line were it not
attainted in 1614. Lord Tyrconnell's youngest child,
Mary Stuart O'Donnell, was born in England around 1607. After her father's death,
King James VI and I, the first Stuart King of England, gave her the name Stuart in recognition of their common Stuart ancestry – they were ninth cousins – hence she was known as Mary
Stuart O'Donnell. She was descended, through her mother, from the Stuarts. Mary was raised by her mother in the Kildare lands in Ireland until she was twelve years old. In 1619, Mary was sent to live with her grandmother, Lady Kildare, in London, where Lady Kildare aimed to educate the girl and make her her heiress. == Portraiture ==