According to Qatar's foreign ministry, fighting will pause for at least four days. Fifty hostages that were taken from Israel will be exchanged for 150 Palestinian prisoners.
RELATED: Israel-Hamas War: Timeline and key developments
There will also be an increase in humanitarian aid sent to Gaza.
Southwest Houston psychologist Dr. Alan Kellerman's cousin, 23-year-old Eitan Mor, is among those presumed taken by Hamas.
"We need hope, but this first group of hostages are gonna be mainly women and children," Kellerman said. "If there ever is a complete hostage release, somebody like Eitan, if he's still alive, and hopefully he is, will be one of the last people being released."
Kellerman said Mor was working security at the Nova music festival when Hamas carried out the massacre on Oct. 7. He and a friend were working to help those injured, facilitate evacuations, and hide bodies to ensure proper burials when they disappeared.
"How do you cope as parents? How do you cope as grandparents? How do you cope as siblings with not knowing whether your family member is dead or alive and whether you'll ever see them again?" Kellerman asked.
RELATED: Israel and Hamas call a truce to free hostages in swap for prisoners, and allow more aid into Gaza
He said the family hopes that, at the very least, they will learn more about Mor's condition from the Red Cross - which is facilitating the exchange.
For more updates on this story, follow Shannon Ryan on Facebook, Twitter and Instagram.