A tweet showing the picture of Alpha the service dog has gone viral.

He's had Alpha for three years and said the dog is not only a loyal companion, but a lifesaver. Using his keen sense of small, Alpha alerts when AJ Schalk's blood sugar drops, prompting him to see the nurse for help.

"He did. He made it on BuzzFeed. One tweet. Their tweet went viral. Here I am," said Schalk, 16, a junior at Stafford High School.

"There's definitely times I'm referred to as the kid with the dog," said Schalk.

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The black dog is such a part of the school, that incoming yearbook editor Grace Fuller thought he deserved a place of honor in the student section, right next to AJ.

"Just as much as a student as anybody else is," said Fuller. She's getting lots of good publicity about Alpha's picture. "Everybody's really loved. That's like the favorite part."