By Ashley Fantz, CNN

Nearly 20 years ago, 76 people lost their lives during an FBI raid near Waco, Texas. CNN's Drew Griffin looks at those events at 8 ET/PT and 11 ET/PT Sunday night in "Waco: Faith, Fear & Fire."

Waco, Texas (CNN) - Sheila Martin's children burned alive. God, she says, wanted it that way.

"I don't expect you to understand," she says, leaning her bird-tiny frame against a full shopping cart in the nursery aisle at a Super Walmart. Her pink shirt, flats and purse match the lilies, hydrangeas and clusters of jasmine she's buying.

"Oh, look, they have forget-me-nots!" She caresses the blue petals and, like a child, puts her nose in the plant and inhales.

"These will be perfect for the memorial."

On Tuesday, Martin and a handful of other surviving Branch Davidians will gather at a hotel off a freeway in this dusty Central Texas town to remember the federal siege on their religious compound, an event that has become synonymous with the word Waco.

On that day in 1993, a 51-day standoff between the armed Davidians and agents with the Bureau of Alcohol, Tobacco and Firearms and the Federal Bureau of Investigation ended in a fire and the deaths of at least 76 people. Among them were Martin's husband and four of her children.

Read the full story here.