Question: What is the date of death of John I, Count Of Ponthieu's father?
Answer: 25 December 1147

John I of Ponthieu (– 1191) was the son of Guy II of Ponthieu and succeeded him as Count of Ponthieu in 1147. Guy II of Ponthieu (–25 December 1147) was the son of William III of Ponthieu and Helie of Burgundy.