While his parents were out having dinner early last month, the young boy's babysitter suffered a "grand mal" seizure, which causes a loss of consciousness and violent muscle contractions.
Pimentel could have panicked, but didn't. Instead, he was brave enough to dial 911 and get help.
"I wasn't too afraid," said Diego. "I got the phone and was walking around while waiting for somebody to answer. They said, '911.'"
Lance Kremer of L.A. County Fire said "grand mal" is a full blown seizure.
"You will have some tightening and full muscle contractions throughout the whole body," said Kremer. "If you are not used to it, it can be a scary sight. I could not imagine a 7-year-old watching that, and still remain calm enough to call 911."
The young hero's parents said they couldn't be prouder.
"We smiled and cried. You get that sense of pride that just takes over as parents," said David Pimentel, Diego's father.
"If I didn't call 911 and got scared then she would have probably died," said Diego. "I am happy that I called 911 and saved her life. She came over to my house a couple of days ago and got me a bumblebee card because I saved her life."
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