And Sarah's doctor says she seems to improve by the day.
Sarah, who was was in a hit-and-run accident when she was 18 that left her in the coma-like state, began speaking, out of the blue, a week ago. Doctors have no explanation.
Jim Scantlin, Sarah's father, told The Early Show co-anchor Harry Smith that, before that, his daughter was "basically unresponsive, in the regular sense of the word 'alert.' She was able to do eye contact and was very aware of her surroundings, but otherwise, physically, she was completely incapable of doing anything."
Sarah's mother, Betsy Scantlin, says Sarah actually started to make some noises a couple of years ago. "We didn't have any idea what that meant," she said to Smith. "We just knew it was a noise that she hadn't made for 18 years, and the people -- it's kind of like having a baby. You kind of learn to know the sounds, and they could kind of tell whether she wanted her TV changed or she was hurting or something, but otherwise, nothing."
Jim recounted the phone call he and Betsy got, informing them of the unimaginable: "It was amazing. I'm in the living room. Betsy was in the computer area, and the phone rings, and I'm immediately aware that it's the nursing home…where (Sarah) resides.
"And suddenly, I'm aware that there's a profound, distinct difference. Rather than speaking about Sarah, it became very clear she was speaking to Sarah. It was the most amazing feeling in the world."
Besty says she's "still stunned" to be hearing Sarah's voice again. "There's just no words. Twenty years ago, I cried a lot. This week, all I've done is laugh because, when I heard her say, 'Hi Mom,' I said, 'Sarah, is that you?' And she said, 'Yeah.' And all I can do is just say -- I've just laughed ever since, because it's just so amazing."
What's more, Jim says Sarah is showing "uncanny recall. It's amazing how -- considering how severe and profound her injury was, her ability to recall -- it's astonishing."
Sarah's doctor, Bradley Scheel, adds that, "It's just been amazing. We're all thrilled. And it seems, almost from day to day, she's able to make more responses. We're really anxious to see how she does from here."