This is the adorable moment a tot explained his type 1 diabetes to his mum - at just 20 months old.

Bain Brandon was diagnosed in August of last year when he was just 12 months old.

Marlee Brandon, 27, has been teaching her son about his care in simple terms since his diagnosis.

But Marlee was shocked when her 20-month-old son was able to explain parts of it to her.

In the sweet video, Marlee asks Bain what he wears and he immediately replies "pump."

She then asks why, and Bain answers "diabetes."

When asked what she gives him when his blood sugar is high, Bain confidently responds "insulin."

Marlee, a speech-language pathologist from Starkville, Mississippi, said: "I was shocked. When he said ‘insulin' like it was no big deal, I couldn't believe it. "

"It took me so long to understand everything myself, and here he is, just 20 months old, already knowing so much."

Marlee credits her background as a speech therapist for Bain's impressive communication skills.

She explained that she always talks to him using simple two- or three-word phrases that he can understand.

Marlee said: "Even though he's only one, I talk him through every step—changing his pump, checking his blood sugar, giving insulin shots—using simple words he can understand. "

"I make sure to emphasize words like 'blood,' 'shots,' 'insulin,' and 'pump' so that he can understand them and use them easily."

"But seeing him talk about it so clearly at just one year old truly blows me away. "

"He's very brave and very curious. Of course, some days are harder—he's only one, but most of the time, he's happy to help and understands why we have to do everything."