(m. 1911 – 1922)
Rupert Georg von Trapp (1 November 1911 – 22 February 1992)
Agathe Johanna Erwina Gobertina von Trapp (12 March 1913 – 28 December 2010)
Maria Agatha Franziska Gobertina von Trapp (born 28 September 1914)
Werner Ritter von Trapp (21 December 1915 – 11 October 2007)
Hedwig Maria Adolphine Gobertina von Trapp (28 July 1917 – 14 September 1972)
Johanna Karolina von Trapp (7 September 1919 – 25 November 1994)
Martina von Trapp (17 February 1921 – 25 February 1951)
Von Trapp was first married to Agathe Whitehead, a niece of St John Brodrick, 1st Earl of Midleton and a granddaughter of Robert Whitehead, who invented the modern torpedo. Agathe christened his first command, the U-boat U-6.
Agathe's inherited wealth sustained the couple and permitted them to start a family. Their first child, Rupert, was born on November 1, 1911, at Pola. The family lived at Pina Budicina 11.
The marriage produced six more children: Agathe, also born at Pola; Maria Franziska; Werner; Hedwig; and Johanna; all born at Zell am See at the family home—the Erlhof—and Martina, born at Klosterneuburg at the family home, the Martinsschlössel.
On September 3, 1922, Baroness von Trapp died of scarlet fever contracted from her daughter Agathe. The family purchased a villa in Aigen, a suburb of Salzburg, and moved in 1924.
About 1926, Maria Franziska was recovering from an illness and was unable to attend school, so von Trapp hired Maria Augusta Kutschera, from the nearby Nonnberg Abbey, as a tutor.