Cassie Goldstein remembers her mom Katherine Goldstein (Katie) enjoying the Fourth of July parade in Highland Park, Ill. Only one of them made it out alive.

Katie (64), was among seven victims. Robert Crimo III22-year-old slugger shot shot after shot at people in the crowd during the Chicago holiday celebration. Over three-dozen people were injured.

Before the massacre began, Katie was happily waving to the parade participants. Cassie told NBC News’ Lester Holt“Every floating object that passed by she waved at them.”

When the gunman started firing, Cassie, 22, initially thought the sound was firecrackers across the street. She recalled, “Then, I looked up and saw the shooter firing down on the children.” I told her it was a shooter, and she needed to get up. We ran together and I was right next to her.”

Cassie added, “He shot him in the chest and she collapsed. I was certain she was dead. I simply told her how much I loved and couldn’t quit. He continued to shoot at me and everyone else.