Yarden Bibas, held hostage by Hamas since October 7, will mark his second birthday as a hostage on Thursday, the Hostage Family Forum said.
Bibas is the first of the hostages taken on the 7 to mark a second birthday as a captive, the forum said, adding that they hope he will be the last to hit this milestone.
His family will mark his birthday with an event in Tel Aviv's Hostage Square, and Bibas' sister Ofri will speak at the event, the forum added.
Bibas's family - his wife Shiri and two young children Kfir and Ariel, were also taken hostage on October 7 and are still held captive.
The youngest of the remaining 101 hostages in Gaza
Kfir and Ariel, are among the youngest Israelis still being held hostage by Hamas in Gaza. Kfir is just one years old. His brother is five years old.
Hamas has claimed that Shiri, Kfir, and Ariel have died, although an external party has not confirmed this, and false claims have been made in the past about the status of the hostages.