Sir Thomas Hoo the father distinguished himself by service at the Battle of Agincourt as Knight to Thomas Lord Camoys, commander of the left wing of the English army. At much the same time he also became father of the younger Thomas Hoo, half-brother to Lord Hoo, who was born in 1416 and was associated with his brother in life and in posterity. In June 1420 Sir Thomas the father and two others were entrusted to ensure the safe passage of the Duke of Bourbon to France, and in the August following, Sir Thomas died at the ancestral home of Luton Hoo, Bedfordshire. The widowed Dame Elizabeth remarried to Sir Thomas Lewknor of Horsted Keynes (c. 1392–1452), as his second wife, and became the mother of his younger children.