Ms Qasawaad was 12 years old when she witnessed soldiers drag the males in her family out of their home in the middle of the night on 28 January 2013. They were among 48 members of her family seized in a raid, she said.
Another of her brothers had already been killed fighting Assad's army in 2012, she said, during a civil war that broke out after the Arab Spring protests in 2011.
"No words can describe the overwhelming anguish that consumed us at that time," she said.
She has not seen her male family members since then - but released prisoners said they heard their names from inside Saydnaya, she said.
Her grandfather, who was born in 1939, would now be elderly, while her father was born in 1962, and her brothers in 1989 and 1994.
Ms Qasawaad said that after the fall of Assad's rule and the liberation of prisoners, her family is feeling "a mixture between laughter and tears".
"We don't know what will happen next, all we can do is keep searching," she said. "We hope we have this spark of happiness again in our lives, because it was swept away with the day that they have taken them."
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