One hundred and three days after Omer Neutra was taken prisoner by Hamas, his parents, Ronen and Orna, found themselves in the basement of the United States Capitol, looking for an exit. Andrea Mitchell, the NBC News journalist, stood with them, eager for an interview. Beside Ms. Mitchell were two Senate staff members, with orders to deliver the Neutras to meetings with their bosses.

It would be the second media interview of the morning for the Neutras and for Yael and Adi Alexander, whose son Edan is also held captive by Hamas. The two families have worked together for months to build political pressure to free their sons, an effort that on this day would include meeting privately with Joni Ernst, a Republican senator from Iowa, and gathering with dozens of members of Congress for a candlelight vigil.

“I have walked more distance in these corridors than I have in my own house,” Ronen Neutra, 59, said of his experience the last four months. “I can’t believe this is our life.”

Hamas took more than 240 people captive when it attacked Israel on Oct. 7. About 100 hostages, most of them women and children, were released during a cease-fire in November, and at least 30 others are believed to have died in captivity, according to Israeli officials. That may leave around 100 alive, most of them men who are Israeli citizens.

Those who remain include a number of Israel Defense Forces soldiers, like Mr. Alexander and Mr. Neutra. The young men, dual American-Israeli citizens who both grew up a short train ride from Manhattan, were serving together on the same military outpost the morning of the attacks.