A letter from the future King Edward VIII describing his recently deceased brother as an "animal" is coming to auction.

Prince John, the sixth and youngest child of George V and Queen Mary, died in 1919, aged just 13, after experiencing a severe epileptic seizure.

'He's been practically shut up for the last 2 years anyhow'

Suffering from epilepsy and a mild form of autism, John, who is Queen Elizabeth II's uncle, had been sent to live in a cottage on the Sandringham Estate, away from the rest of the royal family - and rarely saw his mother and father.

George V also kept him away from public events, for fear John's condition would be seen as a sign of the royal family's weakness.

In the letter, penned just two days after John's death, the future King Edward VIII tells his mistress, Freda Dudley Ward:

"He's been practically shut up for the last 2 years anyhow no one has even seen him except the family + then only once or twice a year + his death is the greatest relief imaginable or what we've always silently prayed for."

He then adds:

"I'm terribly sorry for my sister who was going to a lot of parties in Feb. tho somehow I don't think this mourning will last very long as I think the funeral was to-day; it looks to me as if as little was being made of it all as possible…no one wld. be more cut up if any of other 3 brothers were to die than I shld be but this poor boy had become more of an animal than anything else + was only a brother in the flesh and nothing else."

Edward would later abdicate the throne to marry divorcee Wallis Simpson.

The letter has a $30,000 high estimate and auctions online at Julien's on June 26.

We are able to offer this signed photo from Prince John. A remarkable piece of royal family memorabilia, at a fraction of the price of King Edward's letter.

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