Complex sentence: During his childhood, he met his future wife, Annette Tilleman (or Tillemann; born June 27,1931), then using the name Agnes Ethel Seymour, whose family had managed to escape to Switzerland, using Swedish passports issued by Raoul Wallenberg.
Split into simpler sentences: During his childhood, he met his future wife, Annette Tilleman (or Tillemann; born June 27,1931), then using the name Agnes Ethel Seymour. Her family had managed to escape to Switzerland, using Swedish passports issued by Raoul Wallenberg.