Discussions are underway about Monday's hostage list on fourth day of truce. Catch up on the latest

Monday is the fourth — and possibly final — day of the truce between Israel and Hamas. But today's hostage handover is throwing up a few challenges.

There are a number of ongoing issues, three sources briefed on the discussions said, including ensuring that children on the list are not released without their mothers or grandmothers who might also be in captivity. As part of the deal, family members are not meant to be separated during the release. That deal was already violated when Hamas released one hostage without her mother on Saturday, according to an Israel Defense Forces spokesperson. 

Israel, Hamas and the United States, mediated by Qatar, are currently working through those issues, according to the sources.

While 58 hostages have been released from Gaza since Friday, including 4-year-old American-Israeli Abigail Edan, it is unclear whether additional American hostages will be released from Gaza on Monday, the White House said.

There is also the possibility that the truce could be extended beyond Monday, with both sides indicating their interest in continuing the pause in fighting. No such deal has been announced, but the agreed-upon truce already includes a provision for an extension of one extra day for every 10 hostages Hamas is ready to free.

Here's what you need to know now:

• Dozens of hostages not held by Hamas: More than 40 of the hostages taken from Israel into Gaza on October 7 are not currently held by Hamas, the group that launched the attack, a diplomatic source briefed on the negotiations told CNN Monday. That creates a complication because the truce agreement calls for Hamas to hand over hostages in exchange for Palestinian prisoners held by Israel – which means Hamas must have the hostages to hand over.
• Unclear if Americans will be freed: Two American women had been expected to be released on Monday but that appears to be uncertain, according to three sources briefed on the discussions. “We just don’t know right now,��� John Kirby, the National Security Council spokesman told CNN.
• Hostage knew about daughter's fate: An Israeli woman released by Hamas knew her daughter and husband had been killed on October 7 while she was held hostage, her brother has said. Chen Goldstein-Almog’s daughter Yam was 20 years old when she was killed. Her husband Nadav was 48 years old.
• Aid worker in Gaza feels safer: An aid worker living in Gaza told CNN on Sunday that the pause in fighting has given people the opportunity to "walk safely in the streets," check on their family members and homes, and grieve the loss of loved ones.
• Top EU diplomat calls for peace: Josep Borrell, the EU's foreign policy chief, said the initial four-day truce was an “important first step” towards a “political solution," but that the EU needed to start looking for a more long-term solution.
• Aid into Gaza: The Palestinian Red Crescent Society (PRCS) reported the delivery of 150 trucks of aid to northern Gaza, spanning from the start of the truce on Friday until Sunday evening. The aid in the trucks includes food, water, baby formula and blankets, the PRCS stated, adding that this assistance would benefit thousands of people in desperate need.