 When Catherine was pregnant in the spring of 1548, she had become concerned enough about her husband's flirtatious relationship with Elizabeth that she sent Elizabeth away to live with Anthony Denny and his wife, Joan Champernowne (Kat Ashley's sister), in Hertfordshire.In June 1548, Catherine and Thomas Seymour moved their household from London to Sudeley Castle, the property granted to Seymour when he became Baron Seymour of Sudeley.In September 1548, Catherine gave birth to a daughter, Mary Seymour.