Herzl Shaul, the father of Staff Sgt. Oron Shaul, who was killed in Operative Protective Edge in 2014 but who is officially listed as "missing" because Hamas is refusing to return his remains to Israel for burial, has died of cancer at age 54. Throughout his battle with intestinal cancer after being diagnosed a year ago, Shaul kept up his fight to have his son's remains brought back to Israel. Shaul, who died on Friday, is to be laid to rest at 5 p.m. Sunday in the cemetery at Poria Illit, near the Sea of Galilee in northern Israel. Shaul claimed more than once that he had been stricken with cancer because of the suffering he had endured as a result of Oron's death and the agonizing uncertainty of when the family would be able to secure some measure of closure through a proper burial. A month prior to his death, Shaul was hospitalized at Sheba Tel Hashomer Medical Center as his condition deteriorated. His widow, Zehava, and their children, Aviram and Ofek, were by his side. Hours before his death, Shaul asked Aviram to promise that he would not rest until his brother was returned to Israel. "I very much wanted and prayed to [be able] to see Oron brought back, but I didn't have any more strength. They exhausted me and broke me. I'm asking you to promise me that you won't break and you'll bring Oron back to your mother," Shaul told his son. "Call IDF Chief of Staff [Lt. Gen. Gadi Eizenkot] and remind him that the Golani [Brigade, of which Eizenkot is a veteran] sent Oron into battle in Shujayyia, and he should make sure that Golani brings him home," Shaul instructed Aviram. President Reuven Rivlin extended his condolences to the family and said, "We feel the Shaul family's pain over the death of Herzl, who was a source of strength and determination in the struggle to bring Oron home. At our last meeting, I hoped that Herzl would gain strength and overcome his illness. The State of Israel will continue to do everything it can to fulfill its responsibility and bring Oron home to be laid to rest alongside his father, Herzl." Prime Minister Benjamin Netanyahu said, "My wife, Sara, and I are deeply sorry about [Herzl's] tragic death. In our meeting with Herzl, we saw a strong man who was devoting all his time and effort to fighting for his health and fighting to return the body of his son, Oron. We share in the family's sorrow in the name of the people of Israel, and promise that we will continue to operate at every level to bring Oron back for proper burial. These efforts will not stop until he is brought home." Defense Minister Avigdor Lieberman said, "Herzl did everything he could to bring his son Oron home, and I regret that he did not see that happen before he died." Eizenkot also extended his condolences to the family, saying "I'm sending a big hug to Zehava and the rest of the family at this difficult time." At the same time, another bereaved father died on Friday, this time by his own hand. Nearly 25 years after his son Haim was killed by friendly fire during an ambush in Lebanon, Aryeh Bar-Natan, 85, committed suicide on his son's grave in the military section of the Mount Herzl Cemetery in Jerusalem, which he had been visiting daily in recent years. Bar-Natan, one of the founders of the Mitzpe Yericho settlement, could no longer bear the pain of his son's death. The late Haim Bar-Natan, like Oron Shaul, was a combat soldier in the Golani Brigade. According to relatives, the fact that Bar-Natan had been battling cancer and his health had deteriorated recently, also contributed to his decision to end his life. Mitzpe Yericho resident Moshe Eyal said that Bar-Natan had been a special figure in the community. "Aryeh was one of the core founders of the settlements, which was mixed -- secular and religious. After the core of founders split, he decided to remain in Mitzpe Yericho as the only secular resident," Eyal said. In the years since his son was killed, Bar-Natan worked to honor his memory. He planted a memorial forest and had a road named after Haim, who was his and his wife, Esther's, only son. After Haim was killed, his father added the words "Avi [Hebrew for 'father of'] Haim" to his own name. For years, the Bar-Natan family waged a legal battle against the commanders they saw as responsible for Haim's death. "All these years, he fought the system and couldn't beat it," neighbors from Mitzpe Yericho said. Bar-Natan was laid to rest on Sunday morning.