United Kingdom, Sept. 21 -- The late Princess Diana's brother believes she had "very severe ADHD".

Earl Charles Spencer was diagnosed with the neurodivergent condition, which can cause trouble focusing, hyperactivity and impulsive behaviour, as an adult and he can see parallels between his own behaviour and that of his late sister.

The earl is also convinced Diana, who died in a car accident in 1997, had the learning disorder dyslexia because she struggled at school.

He told People magazine: "Look, Diana was born in 1961, and certainly the private school system in England was not tuned into children's needs as they are today.

"I think Diana suffered from dyslexia. She found spelling and word orders and letter orders quite tricky.

"I ...