 He was named as part of the Hall of Fame by the International Swimming Federation in 2009.Yldefonso's unorthodox style in swimming which would be later known as the "Yldefonso Stroke" has been adapted by pint-sized swimmers, especially those from Asia, particularly the Japanese.Teófilo Yldefonso also had a daughter named Norma Yldefonso who competed at the 2nd Asian Games held in Manila, Philippines and won a silver medal in the 100m butterfly event.