CHICAGO (WBBM NEWSRADIO) — Niles West High School has welcomed a very big, and very furry, addition.

His name is Chief, and he’s a 9-month-old Great Dane.

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Niles West first service animal Chief, a 9-month-old Great Dane takes a nap during an afternoon math class. (Photo: Sammy Butera/Niles West News)

Chief is the first service animal to walk the halls of Niles West. He assists a student who suffers from post-traumatic stress disorder (PTSD) and anxiety.

Dr. Antwan Babakhani, Assistant Principal of Student Services, has played a pivotal role in getting Chief into the school. He says Chief needs to be the size he is because he has to be able to carry the student from class if need be.

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“The type of service that this dog provides for this student requires physical thrust or pull, and a smaller dog won’t be able to provide that type of support,” he said.

Babakhani added that Chief is extremely well-behaved, and has seamlessly blended into the daily routine at Niles West. “He has an amazing presence at the school; he’s also very endearing.”

Babakhani says Chief is a highly-trained service dog as long as he wears his service vest. As soon as the vest comes off, however, Chief is as playful and energetic as any other puppy — just quite a bit larger than most.

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“When Chief puts his vest on, he literally changes personalities. He goes into this disciplined work mode,” Babakhani said. “With his vest off, he’s like any other puppy. I’ve never seen anything like it.”