Wikipedia
Montuherkhopshef or Montuhirkhopshef was a Prince of the 20th Dynasty of Egypt and one of the sons of Ramesses III and Iset Ta-Hemdjert. He was thus a brother of Ramesses IV, Ramesses VI, Ramesses VIII and an uncle of Ramesses V and Ramesses VII.
He was the "First Charioteer of His Majesty", and married the lady Takhat who bears the prominent title of "King's Mother." This development supports the hypothesis that they are most probably the parents of king Ramesses IX since no other Ramesside king had a mother by this name.
Since Montuherkhopshef never became Pharaoh unlike his brothers and nephews, his date of death can be placed prior to Year 22 of Ramesses III (1164 BC) since his brother Ramesses IV is known to have been designated as Egypt's crown prince in this year.