A 4-year-old boy with a passion for medicine gave a medical school student a run for her money at a grocery store.

Parnia Salehi, 24, told Hot Topics she was shopping at a Trader Joe’s store on Monroe Drive in Atlanta Tuesday when a 4-year-old boy named Anson Wong commented on her Morehouse Medical School T-shirt.

He overheard his dad talking to her about the school and didn’t hesitate to join the conversation.

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“Anson was sitting in the cart and asked, ‘Oh, what kind of doctor do you want to be?'” the medical school student recalled. “So obviously my first reaction was, ‘Oh, this little kid knows the different types of doctors?’”

Impressed with the boy’s curiosity, Salehi responded that she was interested studying the brain.

“His response was, ‘Oh, so you like the nervous system. I like the immune system,'” said Salehi.

Salehi was shocked when Anson started explaining the nervous system in detail.

“It was at least graduate level physiology,” said Salehi. “Such a random thing for a little kid to be passionate about -- the immune system.”

With his parents’ permission, Salehi started recording video on her cell phone as Anson explained the body’s immune response system. Anson’s dad can be heard in the video.

“I was trying to convince him that the nervous system is cooler,” Salehi recalled with a laugh.

Anson wasn’t having it.

In the video, Salehi asked Anson if the immune system is still his favorite.

“Yes,” Anson responded with a dreamy, far-off look. “Always. Forever.”

Anson’s mom, Alice Wong, told Hot Topics her son has always been a quick learner. At just 16 months old, he was reading three-letter words, and by 18 months, he was able to read short sentences.

“I feel like I don’t spend any more time teaching him than other moms,” said Wong. “I give him material, but it’s so quick for him to absorb all this stuff.”

Wong has shared videos to YouTube showing her son reading in English and Spanish.

“He’s good at every subject. You can ask him anything about life science, geology, medical stuff, how photosynthesis works, the weather,” said Wong.

Wong said her son has big ambitions for the future.

“So far, he has voiced to us that he wants to be a doctor, a scientist, an astronaut and the president of the United States, because he wants to save the planet. He wants to help people,” said Wong.