Survivor of horror smash can't remember dead family

A woman whose husband and young child died in a horrific car accident in the US has no memory of the incident or her dead family.

Florida authorities say Ivelisse Martinezz, 27, had no recollection of the appalling smash, caused by an elderly woman who failed to brake, that claimed the lives of 35-year-old Jose Vargas Rosario and their son, Brayden Vargas in Altamonte Springs last week.

"She was informed of the passing of her husband and her son – she does not remember the crash and at that time, didn’t remember the family members either," Altamonte Springs Police Lieutenant told WESH.

Emergency Medical Services Director Dr Todd Husty says it's not clear precisely what the cause of Ms Martinezz's amnesia is, but that her memory will likely return.

"[Amnesia] almost always resolves, just sort of spontaneously, just out of the blue – suddenly people start remembering," he said.

"It’s likely she’s had head trauma. That’s the most common reason for someone to have amnesia would be head trauma. But physiological trauma can do that too."

Police are still investigating the crash; the woman who caused it, 75-year-old retired teacher Cynthia Guthrie, has not been charged.