William I of Württemberg
On 24 January 1816, in Saint Petersburg, he married his first cousin, Grand Duchess Catherine Pavlovna of Russia (1788–1819), daughter of Emperor Paul I of Russia (1754–1801) and Princess Sophie Dorothea of Württemberg (1759–1828). The couple had two children:
Infanta Maria Doroteia of Portugal
Maria Doroteia of Braganza ("Maria Francisca Doroteia Josefa Antónia Gertrudes Rita Joana Efigénia"; 21 September 1739 – 14 January 1771), was a Portuguese "infanta" daughter of King Joseph I of Portugal and his wife Mariana Victoria of Spain.