Tawfiq Diam is emotional because it's the first time he's been able to speak freely about what happened to his family back in 2018, in Douma in the Eastern Ghouta suburb of Damascus.
"If I'd spoken out before, Bashar al-Assad's forces would have cut off my tongue. They would have slit my throat. We were not allowed to talk about it," he says.
Tawfiq's wife and his four children aged between eight and 12 - Joudy, Mohammed, Ali and Qamar - were killed in a chemical attack on 7 April 2018.
The Organisation for the Prohibition of Chemical Weapons (OPCW), a global watchdog, said in a report last year that it believed a Syrian air force helicopter departed from the nearby Dumayr air base shortly after 19:00 that day and dropped two yellow cylinders which hit two apartment buildings, releasing highly concentrated chlorine gas.