Rowling reveals the real reason why The Dursleys hated Harry so much.
J. K. Rowling - author of the seven Harry Potter books - is often giving fans an insight into background information on the characters from the novels.
Sometimes these snippets please the fans, sometimes they don't.
In her latest five updates she has revealed why her auntie and uncle, muggle meanies Vernon and Petunia Dursley made the boy wizard's life an utter misery.
Rowling wrote on the website Pottermore explaining what caused the split between Harry's parents and his aunt and uncle.
Vernon and Petunia Dursley.
The jist of the problem was down to money.
Problems started at a meal that was meant to introduce Lily to her sister's fiance, Vernon. Lily brought along her boyfriend James Potter, who if you remember correctly was one who enjoyed mocking or making others uncomfortable.
"James was amused by Vernon, and made the mistake of showing it," Rowling explains. "Vernon tried to patronise James, asking what car he drove. James described his racing broom.
"Vernon supposed out loud that wizards had to live on unemployment benefit. James explained about Gringotts, and the fortune his parents had saved there, in solid gold.
"Vernon could not tell whether he was being made fun of or not, and grew angry. The evening ended with Vernon and Petunia storming out of the restaurant, while Lily burst into tears and James (a little ashamed of himself) promised to make things up with Vernon at the earliest opportunity."
There was never a reconciliation and the split between the sisters worsened. In fact neither sister attended the other's wedding.
In fact the last time Vernon and Petunia heard from Lily and James - before their death - was from a letter announcing the birth of Harry, who was played by Daniel Radcliffe, – which Petunia threw away.
Eddie Redmayne is due to star in the Potter spin-off film.
And so basically when they had to then take Harry in and look after him they were constantly reminded of the feud as he brought back too many memories.
When they were forced to take the baby in, he always brought back too many memories of his father and the family feud.
These extracts from Rowling have been filling fans in from missing the Harry Potter novels.
However a spin-off film called Fantastic Beasts and Where to Find Them is getting fans excited all over again.
The film, which Rowling submitted the script for in November last year, will star Eddie Redmayne and Katherine Waterston.
Let us know what you think of Rowling's latest Pottermore installment via @heatworld Twitter and Facebook.